Haikyū!! Wiki
Haikyū!! Wiki
Someone who can't see the opponent standing right in front of him, can't defeat the opponent that lies beyond!

Hajime Iwaizumi (Japanese: 岩泉 (いわいずみ) (はじめ) Iwaizumi Hajime) is a third-year student from Aoba Johsai High. He was the volleyball team's ace, vice-captain, and a wing-spiker. He is Tōru Oikawa's childhood friend.

After graduating high school, Iwaizumi went to college and majored in sports science. In 2021, he is an athletic trainer and is seen working with the Japanese National Volleyball Team.


Iwaizumi has dark, spiked-up hair, and thin eyebrows. His eyes are dark brown in the manga, olive green in the anime adaptation, and grey in the Haikyuu!! smartphone game. His hair is black in the manga and in the Haikyuu!! smartphone game, but dark brown in the anime. More often than not, he's shown to hold a serious or irked expression.

While playing volleyball, Iwaizumi wears a standard Aoba Johsai uniform with number four on it. He is otherwise shown wearing an Aoba Johsai school uniform consisting of khakis with dark brown details, a lavender-colored button-down shirt, a dark red tie, and a white blazer. Iwaizumi's uniform appears to be missing the cream-colored vest that goes with the rest of the uniform and appears to be slightly disheveled, with his tie loose around his neck and his shirt left untucked.

In the anime adaptation, Iwaizumi is seen wearing an outfit which consists of a pair of jeans with an oversized dark blue denim jacket over a grey hoodie.

Post-timeskip, Iwaizumi's appearance has changed very little.


Iwaizumi is a stubborn but reliable teammate, often filling in Oikawa's spot as a morale booster if needed. He acts supportive to all, including Tobio Kageyama, and calls Oikawa out for his childish antics. He often resorts to violence with Oikawa whenever he teases or provokes him, but this does not change the fact that he cares immensely for him; as shown when he makes an effort to stop Oikawa from either working too hard or losing confidence.

Iwaizumi's firm-yet-caring attitude has led some members of the Aoba Johsai team to look up to and respect him. His underclassmen often gravitate towards him and he is seen giving calm and light-hearted advice to Kindaichi, which can contrast to how he treats Oikawa. He is also very respectful and does not treat his rivals coldly, as Kageyama still treats him respectfully and Iwaizumi has acknowledged his skills.

It is also seen through some extras by Furudate that, while Iwaizumi can be strong and intimidating, he also has quite the goofy side where he loves monsters and gets excited when he finds an "Oikawa" fish in a book to make fun of Oikawa with[1].


Oikawa and Iwaizumi s1-e24-2.png

Since childhood, Iwaizumi has been close friends with Oikawa. The two are often shown watching volleyball matches on television and playing volleyball in their free time. When they were a little older, Iwaizumi accompanied Oikawa to a match in Sendai between Argentina and Japan. He witnessed Oikawa meet with Jose Blanco and saw his friend's dedication to become a setter begin at this point.

As they got older, Iwaizumi witnessed Oikawa push himself to become a great volleyball player. However, he soon saw his friend begin to push himself too hard when he found himself to be no match for Ushijima's raw power and brute force or Kageyama's seemingly gifted abilities. One night, Iwaizumi was able to stop Oikawa from striking Kageyama while he was blinded by rage and was able to help his friend see that, while he stood no chance against someone like Ushijima alone, he has a team to rely on that can help him be stronger. From this, Iwaizumi seemed satisfied that Oikawa appeared to be recovering although he occasionally has to keep him in check at times.


Karasuno High Team Formation Arc

As Oikawa was not present for the start of the match, Iwaizumi would lead the team through majority of the practice match. Right before the match is about to start, Iwaizumi, along with Yahaba and Matsukawa express their confusion over why Kageyama decided to attend Karasuno[2].

During the second set, Kindaichi gets frustrated because of Hinata’s decoy trick as well as Tanaka’s taunts. Iwaizumi advices him not to be impatient and not to get dragged into their pace since their own attacks are still working. When a time-out is called, Iwaizumi and the team hear from their coach how Kageyama is giving his spikers the best hittable sets possible and how Hinata is hitting his super quick with his eyes shut. Although Iwaizumi finds the news amazing, he does not linger on it too much.

When the game continues, Iwaizumi is blocked by Kageyama and Tsukishima. When Karasuno reaches set point, Iwaizumi admits that he is starting to worry that they may lose the game. After Karasuno won the second set, the teams are having a small break before the third set when Tōru Oikawa arrives.

Near the end of the third set, Oikawa is switched in and nearly gets Seijoh caught up until Hinata was able to get a one-touch on Kindaichi's spike. As Hinata made his approach for a wide broad attack, Iwaizumi tried to stop him but he was not quick enough to stop Hinata from getting the winning point. After Karasuno left, Iwaizumi listens to Oikawa admitting that Kageyama is a more skilled setter and becomes annoyed at hearing his friend think he is not as good as the first-year. Even as Oikawa tries to convince him that there is possibly no one else who can compare to Kageyama in setting, Oikawa still firmly believes that Seijoh can beat Karasuno since Oikawa knows his team better than Kageyama does and is already looking forward to beating Karasuno in a real match. Iwaizumi again becomes annoyed at Oikawa's antics but is questioned if he himself did not like naturally talented people like Kageyama. Iwaizumi instead answers that pretty boys like Oikawa are what annoy him most and begins hitting Oikawa with volleyballs.


On the first day of the Interhigh Tournament, Aoba Johsai arrives at the Sendai City Gymnasium. As they are entering and are discussing going to watch Karasuno's first match, it's pointed out that Oikawa has slipped away from the group. When it's revealed that Oikawa has been pulled away by a group of fangirl's, Coach Irihata sends Iwaizumi to find the setter. Outside, Iwaizumi finds Oikawa and immediately throws a volleyball at his head. Fearful of Iwaizumi's presence, Oikawa quickly follows the ace inside[3].

As the team makes their way into the gym, Iwaizumi hears Oikawa teasing Hinata and Kageyama and quickly stops him. At this point, they notice that Karasuno now has Asahi and Nishinoya on the team as well as Ukai as their new coach. Just before the match starts, Iwaizumi is amused at the confused looks Hinata is attracting when Tokonami sees that he is playing as a middle blocker and when Kindaichi expresses how this would be their downfall since he himself had done the same.

Although he admittedly dislikes Kageyama, Iwaizumi remarks that Hinata was not doing much in their quick set, rather, Kageyama’s remarkable sets were.

Aoba Johsai vs Karasuno

The evening before Aoba Johsai’s match against Karasuno, Iwaizumi tells Oikawa not to stay up all night watching the recording of Karasuno’s previous match he was holding in his hand. At this, Oikawa sarcastically asks Iwaizumi if he was his mother, and Iwaizumi angrily stares at him, which results in Oikawa telling him that he was going to take care of himself. After this, Iwaizumi yells and insults his friend, which offends Oikawa. The next day, when warming up for their match against Karasuno, Oikawa asks Iwaizumi if he’s trying too hard, but ultimately, it would be useless since none of the girls would be paying attention to him. Angry, Iwaizumi is about to hit Oikawa, but Kindaichi holds him back before he is able to do so[4].

During the second rally, Oikawa seems to be going for a dump but changes his course to set for Iwaizumi at the last minute, and he is able to score. Following this, Iwaizumi tells Oikawa that his set was too low, but Oikawa tells him that he knew Iwaizumi would have been able to hit it either way. When Nishinoya bumps Oikawa’s serve, Iwaizumi gets angry because he wasn’t expecting it. Later on, Oikawa calls for a time-out to explain what he’s figured out about Karasuno’s tactics, and when Iwaizumi tells him that it would seem clear that Aoba Johsai would have figured it out after such an early time-out, Oikawa tells him that he wants Kageyama to panic.

Even after Oikawa tells Aoba Johsai about how to tell which one of Hinata’s attacks is coming, Iwaizumi still has a hard time blocking them as they are still extremely fast. After losing this rally, Iwaizumi tells Oikawa never to say that he could never beat Kageyama as a setter ever again, and when his friend answers back innocently, Iwaizumi angrily glares at him. When Sugawara is subbed in for Kageyama, Oikawa tells Iwaizumi to go for a line-shot, as Sugawara’s block would be easy to surpass as he is shorter[5]. However, when Iwaizumi is about to hit the ball, Tsukishima blocks him, having just switched places with Sugawara, since he knew that he was going to get targeted.

Iwaizumi and Matsukawa s1-e21-2.png

When Sugawara is about to set to Hinata, Iwaizumi and Matsukawa are confused about which quick set it was going to be. Noticing their hesitation, Oikawa yells at the two that it’s because Sugawara is setting, not Kageyama, to which they get mad at themselves. Aoba Johsai just needs a single point before they win the first set, but before that Hinata attempts to spike the ball to the other side of the court, but fails and Iwaizumi bumps it with difficulty. During the time-out for the end of the first set, Iwaizumi admits that he initially thought that Karasuno’s defense only depended on Hinata and Kageyama. After hearing this, Oikawa mockingly tells Iwaizumi not to overthink things as he’ll hurt himself, and Iwaizumi headbutts his friend.

Karasuno is one point away from winning the second rally, however, Iwaizumi spikes against Karasuno, and some spectators notice that Aoba Johsai’s players are really good, but they keep getting forgotten behind Oikawa. Right after, it’s Oikawa’s turn to serve, and both Iwaizumi and Hanamaki in front of him tell him to smash it, to which he answers “I know”. During the same set, Iwaizumi gets blocked, and seeing his frustration Oikawa tells him that Kageyama probably read that. Not long after, Oikawa sets for Iwaizumi, and Takinoue is awed at how in sync the two are. Hinata is about to pull his quick attack, and together, Iwaizumi and Matsukawa try to stop him but fail since he is instead used as a decoy.

Not long after, Daichi tries his hardest to prevent their loss, but gets reminded that Aoba Johsai isn’t either as Iwaizumi saves the ball in a hurry. When Iwaizumi spikes and motivates his team, they are all impressed at how cool he is, but Oikawa ends up insulting him. Despite this, Iwaizumi knows that Oikawa is thinking of Ushijima while Aoba Johsai is just a few points away from winning, but tells him that if he couldn’t focus on his current opponents, he wouldn’t be able to beat Shiratorizawa[6]. In the next rally, Karasuno is waiting for Aoba Johsai’s next move, but at least know that they would be leaning on their ace. However, he is used as a decoy. After Aoba Johsai’s victory, the team gathers around each other and cheer.

Aoba Johsai vs Shiratorizawa

Aoba Johsai advanced to the finals but were unable to claim victory against the reigning champion team, Shiratorizawa Academy. However, unlike the third years of most other schools, Iwaizumi and the others Seijoh third-years would not retire from the team as they wished to have another chance to play against Shiratorizawa and make it to the Spring Tournament.

Tokyo Expedition Arc

Spring High Preliminary Arc

Sometime prior to the qualifiers, Iwaizumi threatens Oikawa if he were to catch a cold. Iwaizumi would once again get on the offense when Kyōtani brings up having defeated by Shiratorizawa another time. As the qualifier tournament is about to begin, Hinata encounters Iwaizumi and Oikawa in front of the men’s bathroom, which startles him. Upon this encounter, Iwaizumi asks Hinata about having defeated Kakugawa and Hyakuzawa in particular. When Oikawa smugly tells Hinata about his upcoming defeat, Iwaizumi tells Oikawa to be more mature. However, tension soon grows high as Ushijima arrives and unintentionally insults Oikawa and Iwaizumi, which provokes them.

Karasuno vs Wakutani Minami

When preparing for their own match, Iwaizumi and Oikawa watch Karasuno’s match for the qualifiers’ second round. When Iwaizumi misses what happens during the middle of the first set, Oikawa explains that there was a collision between Daichi and Tanaka. After this, Iwaizumi is afraid that Daichi might have a concussion. As the captain is subbed out to get medical support, Iwaizumi suggests for Karasuno to go six-two, but Oikawa doubts the possibilities. After this, Iwaizumi can’t recall much from Ennoshita when being asked about his performance during their practice game when he is subbed in.

Aoba Johsai vs Date Tech

During the match, Iwaizumi doesn’t struggle to spike past Date Tech’s blockers. Despite this, he is still not able to score as Sakunami manages to bump it roughly. Not long after, Iwaizumi and Hanamaki both insult Oikawa and they get a remark from him. Later on, Iwaizumi serves and he seems to be able to score a service ace, but ultimately, Date Tech wins the point.

Group s2 e 18 9.png

After Oikawa intentionally sets to Iwaizumi for him to get past the blockers, Iwaizumi tells Oikawa to simply let him fight his own battles, and Oikawa gets intimidated by this comment. When Oikawa sets to him once more, some spectators notice that Iwaizumi isn’t a very big person overall, but Date Tech’s extremely tall blockers make him look even smaller. Despite this, Iwaizumi is able to find a crack in Koganegawa’s defense and manages to score and win the match.

Aoba Johsai vs Karasuno

As the game is about to begin, Oikawa tries to voice his trust in the team only for Iwaizumi, Matsukawa, and Hanamaki to state their trust in him as their captain. Although they are serious in their trust in Oikawa, Iwaizumi and the others warn him to make his first serve of the game count, or else he will owe them and the team ramen after the game. Iwaizumi would later serve, and Karasuno’s back row notice how his serve has gotten better as well, much like the rest of his team. During the end of the first set, Iwaizumi punches Kyōtani, concerned for his teammates’ safety, as Kyōtani had randomly leaped in his teammates’ attack. During the next rally, and the start of the second set, Yahaba, on the sidelines, explains that because Kyōtani had lost every single time to Iwaizumi in every single athletic school tournament, Iwaizumi is the only one who he’ll listen to.

Later on, Oikawa sets, and Matsukawa is used as a decoy for Iwaizumi to score. However, he finds his task more difficult than he thought asYamaguchi receives it with his chest, desperate to stay on the court longer. Iwaizumi clashes against Yamaguchi once more when he scores past him and ends his streak of points. Shortly after, he notices Kindaichi tensing up and tells his junior to focus on the next points rather than the ones they lost. Iwaizumi later wins Aoba Johsai the set thanks to both Kindaichi and Kyōtani being used as a decoy for him to score.

At the start of the third set, Iwaizumi is able to score the first point. When Kyōtani started to become aggressive after Tsukishima had blocked him and called his serve as landing out, Iwaizumi attempted to speak with Kyōtani but Coach Irihata brought Kyōtani out of the game before he could. Once Kyōtani was sent back in after having been confronted by Yahaba, Iwaizumi joins the team in complimenting the second year and celebrating the times he is able to earn them points.

Iwaizumi saves Yamaguchi’s serve by lunging for it and surprises the spectators. Iwaizumi would impressively save another difficult shot when Asahi spikes. After this, Iwaizumi thinks to himself at how he used to think spiking was the greatest thing someone could do however, he learned that saving a shot that a spiker thought was perfect was even more satisfying. Near the end of the set, Sugawara serves, but purposely aims at where Iwaizumi and Watari are standing so it makes Watari wonder whether he should leave it to Iwaizumi. In the end, Iwaizumi gets it but it puts him out of position. After Kageyama pulls a dump, Iwaizumi gets frustrated and yells at how angry Kageyama makes him.

In the final set, Oikawa goes out of the court to set to the ball where Iwaizumi is on the other side. Iwaizumi, happy at that perfect set, slams the ball to the opposing court but Tanaka manages to receive it. Iwaizumi is also of the triple block that read Kageyama’s motion to set to Hinata, but they still fail to block him. After their loss, Iwaizumi blames himself for the loss as he felt he was unable to make his last spike count and believes he is not worthy of being the ace. He gets comforted by Oikawa, Hanamaki, and Matsukawa with pats on the back and joins them and the team in thanking their supporters. Nevertheless, that evening, he has a competition with Oikawa to determine who had the more right to be upset over their loss. Shortly after, the club’s third years all play together. As they are about to wrap things up, Hanamaki senses that Oikawa is about to end off with a happy message to conclude their volleyball career and they all break into tears.

Iwaizumi and Oikawa would soon walk home together. Iwaizumi tells Oikawa that he doubts Oikawa would ever be happy because he can’t see him be satisfied, even with perfection. However, he and Iwaizumi both fist bump and thank each other for being such great partners.

Karasuno vs Shiratorizawa


Iwaizumi would join Oikawa in watching the match between Karasuno and Shiratorizawa. He would spot his friend in the bleachers and call him out on having previously stated that he would not come to the match because he would be upset regardless of who won the match. Throughout the match, Iwaizumi would be surprised at numerous plays made by each team and was also able to determine that Karasuno was able to survive the last set thanks to Tsukishima's return and a plan that the middle blocker had most likely formed while he had been recovering from his hand injury.

Tokyo Nationals Arc

Iwaizumi is seen watching Karasuno’s game against Kamomedai with Oikawa[7].

Final Arc

During his sophomore year in college of studying sports science, Iwaizumi had traveled to Irvine, California for a meeting with Takashi Utsui[8]. While on his way to the meeting, he ran into Ushijima and explained that he was there hoping to intern under Utsui once he graduated college. It was then that he learned Utsui is Ushijima's father. After the meeting, Iwaizumi and Ushijima spoke about Ushijima's performance on the world team and the two looked over video's together. Before they parted, Iwaizumi requested they take a photo together so he could send it to Oikawa.

As of 2021, Iwaizumi is now an athletic trainer and is last seen with the Japan Men's Volleyball Team at the Tokyo Olympics[9].


High School Statistics
Game Sense

Iwaizumi is Aoba Johsai's ace, and his spikes are incredibly strong. He is a dependable player with faith in his own abilities, which leads Oikawa setting to Iwaizumi whenever he feels that he's in a pinch. He is shown to have solid receives; often getting the ball when Shinji Watari, Seijoh's libero, is unable to. Iwaizumi stated that when he was little he only found spiking to be fun, but as he has gotten older he's grateful that he knows the "thrill" of receiving his opponents' flawless hits[10]. It has been noted by Keishin Ukai that Iwaizumi has a powerful serve. Being hit continuously by his and Oikawa's serves throughout a match can be incredibly taxing on their opponents. He is also fearless enough to exploit Koganegawa's technical flaw as a blocker despite his height.

Jumping Reach: 327 cm


  • Spikes: Iwaizumi is known for having powerful spikes that are either difficult to receive or are able to throw his opponent off balance.
  • Serves: Iwaizumi has been stated to have one of the strongest serves on the Aoba Johsai team. He is able to use his serve to put pressure onto opposing receivers.
  • Blocks: Although he is on the shorter side for a blocker, Iwaizumi is still able to position himself in time to either get a stuff block or a deflection. However, when faced against someone of great speed, like Hinata, Iwaizumi can at times fall for decoy attempts or not be able to complete his block.
  • Receives: Iwaizumi is incredibly skilled at receiving. He is able to dig numerous spikes and serves with little trouble and is shown to do whatever he can to save a ball thought to be heading out of bounds.


Aoba Johsai High

  • Tōru Oikawa:
    Friends since childhood, Iwaizumi is Oikawa's closest friend. Knowing Oikawa for so long, Iwaizumi knows him so well that he is able to tell the difference when Oikawa is being genuine or not. Although Iwaizumi often calls Oikawa a variety of insulting nicknames and keeps him in line with threats of physical harm, Iwaizumi still has full faith in Oikawa as the team setter and captain. The two often make a powerful duo that put many teams on edge. Though Iwaizumi often lashes out at Oikawa for his stupidity, he genuinely cares about him and his health, as shown by him consistently reminding Oikawa to take breaks and not overdo himself. Any time that Oikawa appears to doubt himself as a setter, Iwaizumi is quick to remind him of how amazing his skills are. Even after high school, Iwaizumi is shown to still enjoy teasing Oikawa as shown when he sent a selfie of himself and Ushijima to Oikawa.
  • Takahiro Hanamaki: Hanamaki and Iwaizumi seem close and can be seen around each other at times. Hanamaki is usually the one to team up with Iwaizumi when it comes to teasing Oikawa about different things.
  • Kentarō Kyōtani:
    Iwaizumi and Kyotani s2-e21-1.png
    Iwaizumi is the only third year to be respected by Kyōtani after the second-year repeatedly challenged him to multiple athletic competitions and lost to the ace every single time. Because of this, Iwaizumi is usually the one tasked with keeping the Kyōtani in line, either through verbal warnings or physical violence. Despite this, Iwaizumi is shown to support Kyōtani when he makes a good play and when he begins to connect with the rest of the team.
  • Yūtarō Kindaichi:
    Iwaizumi and Kindaichi s1-e6-1.png
    Iwaizumi is shown to be a stable and comforting figure toward the first-year middle blocker. He is able to tell when Kindaichi starts to doubt himself or become overwhelmed with nerves in a tense situation and is able to help keep him calm and clear headed. Like several others on the team, Iwaizumi is looked at as a 'cool' figure to Kindaichi when he says or does something impressive.


  • "Do you think you're fighting by yourself?! You've got to be kidding, you dumbass! If you think how you're doing equals how the team will do, I'll punch you!... There's no one on our team who can beat Ushiwaka one-on-one! However, there are six players on the volleyball court! Even if our opponent's some genius first-year or Ushiwaka, the team with the better six is stronger, you dumbass!" (To Oikawa, Season 1 Episode 22)
  • "Someone who can't see the opponent standing right in front of him, can't defeat the opponent that lies beyond!" (To Oikawa, Season 1 Episode 24)
  • "Don't think about anything unnecessary. No matter what, you only need to focus on the ball in front of you." (To Kindaichi, Season 2 Episode 22)


  • Favorite food: Agedashi tofu
  • Current concern: "Just 1cm more..or 7mm, at least..!" (In regard to his height.)
  • He is the oldest third-year on the team.
  • He is very athletic as shown by him beating Kyōtani in several events such as running, batting, and arm-wrestling[11].
    • Iwaizumi is also shown to be the current arm-wrestling champion of Aoba Johsai.
  • His star sign is Gemini.
  • When combined, Iwaizumi and Oikawa's first names (Hajime and Tōru respectively) form "一徹" meaning "obstinate" or "dauntless".
  • In an illustration on Twitter, drawn by Furudate for Haikyuu’s anniversary, in which Iwaizumi in 2022 is shown, he is seen as an athletic trainer for Birtwistle University in the USA.
  • Iwaizumi's birthday is the death date of Alexander the Great, matching with Oikawa's birthday which is the birthdate of Alexander the Great.
  • Iwaizumi is one of the few characters whose color palette varies in the manga to anime. In the manga, his hair is black and his eyes are dark brown, but in the anime, his hair is dark brown and his eyes are green.
  • Iwaizumi's skills have been commended by Karasuno's players and coaches and his total stats add up to the same total as Ushijima, one of the top 3 aces in Japan.
  • While Iwaizumi is taller than average, he's the shortest of the Seijoh third-years and appears to find frustration in this. In the Haikyuu Cross Team Match game, Iwaizumi states his goal is to grow to 185 cm so he'll be taller than Oikawa (who responds that he will push on Iwaizumi's pressure points so he can't grow taller than him).
    • In the end, Oikawa is the one who surpasses 185 cm while Iwaizumi never cracks 180 cm.[12]
  • There is a running gag that whenever he and Oikawa are in the same camera shot, Oikawa will block Iwaizumi's face somehow; whether it be him holding a peace sign in front of him, or standing directly in front of him.
  • Iwaizumi was voted the top wing spiker by readers in the "Best Lineup" poll with 1240 votes.
  • In the Cross Team Match game, Iwaizumi says he used to capture cicadas during childhood but he always let them go afterward (when asked, he said cicadas had a short lifespan so he took pity on them).
  • In Haikyuu's first popularity poll, Iwaizumi placed 11th with 3,097 votes[13]. In the second, he rose to 9th with 6,111 votes[14].
  • Nomenclature:
    • Hajime (一) - One
    • Iwaizumi (岩泉) - Rock (Iwa) Spring/Fountain (Izumi)