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) was a third-year student from Aoba Johsai High; he was the volleyball team's ace, vice-captain and a wing spiker. He is also Tōru Oikawa's childhood friend and "pillar". After graduating high school, Iwaizumi went to college and majored in sports science. In 2014, he traveled to Irvine, California intending to meet Takashi Utsui, a Japanese trainer he wanted to intern with post-college. As of 2021, he is an athletic trainer.


Iwaizumi has dark, spiked-up hair and slightly thicker than average 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.


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 skill.

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" (a type of fish) in a book to make fun of Oikawa with. 



Knowing Oikawa since early childhood, they both went to the same school, Kitagawa Daiichi Junior High and it's rumored that they've been in the same schools until high school.


They were both bitter rivals of Ushijima, although Iwaizumi didn't seem to take him as seriously as Oikawa did. Iwaizumi constantly kept his friend in check, including the time Oikawa almost hit Kageyama in a moment of blind rage. He often uses violence and somewhat harsh words toward Oikawa but despite all that he still strongly cares for Oikawa. Iwaizumi and Oikawa later attended Aoba Johsai High together, becoming Vice-Captain and Captain respectively by their third year.


Karasuno High Team Formation Arc

Iwaizumi plays in the starting line-up in the practice match between Aoba Johsai and Karasuno. He is initially surprised to see Kageyama on the Karasuno team. Since Oikawa was not there for majority of the match, Iwaizumi acted as captain and kept his team together when it seemed like Karasuno was getting the better of them.


Aoba Johsai vs Karasuno

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

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.

When Karasuno was the first to reach set point, Kyōtani would be sent into the match to try to help Seijoh take the set. However, Kyōtani put too much strength into his spike and unintentionally lost the set. Iwaizumi would be quick to scold Kyōtani for his reckless behavior by hitting him on the head and scolding him. When it was clear that Kyōtani wasn't taking Oikawa's warnings seriously, Iwaizumi made it clear that Kyōtani would be removed from the game if he continued to do dangerous plays. Kyōtani would quickly obey Iwaizumi, to Oikawa's annoyance, and Yahaba reveals to Kunimi that Kyōtani only listens to Iwaizumi because the ace has beaten him in every competition Kyōtani has challenged him to. As the game continues, Iwaizumi is noted to be receiving many of Hinata's spikes. This causes Kageyama to believe that Seijoh has planned to have someone ready to receive Hinata's spikes at all times.

After Yamaguchi is subbed in as a pinch server, Iwaizumi attempt to end his serve but was surprised to see Yamaguchi make a receive with his body although Oikawa would later claim that it was most likely due to luck that Yamaguchi made the receive. After several more of Yamaguchi's serves, Iwaizumi was able to score the point that would stop the pinch server and tie the score. After a few plays, Iwaizumi noticed that Kindaichi was starting to get caught up in his fear of this being the last game for the third years and began hesitating in his plays. Iwaizumi tries to help the first year overcome his emotions by telling him how the team needed him to be calm and collected. Soon after, Iwaizumi makes the final spike that would win the second set for Aoba Johsai.

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.

Once the score reached 21-20 with Seijoh in the lead, Iwaizumi is revealed to have only been interested in spikes when he had first started playing volleyball during his childhood. Over the years, he began to find more joy in receiving an opponents strong spike and making that point his own. Once Sugawara was sent in at the end of the set, Iwaizumi became the setters new target with his serves. Later when Karasuno attempted the synchronized attack, Oikawa would chase the ball as it headed out of bounds and signaled to Iwaizumi that he would be sending him. Iwaizumi was able to hit the set perfectly but Daichi was able to receive it. The ace then attempted to join the triple block to stop Hinata only to be caught off guard when the middle blocker did a block-out against Kindaichi's hand which led to Oikawa being unable to make a proper receive. With this, Seijoh has lost and are removed from the tournament. Despite the comfort their coach tried to provide, Iwaizumi would blame 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 would be comforted by Oikawa, Hanamaki, and Matsukawa with pats on the back and would join them and the team in thanking their supporters.

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.

Final Arc

During his sophomore college year of studying sports science, Iwaizumi had traveled to Irvine, California for a meeting with Takashi Utsui. 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 Olympics.


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, Seijō'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.[1] 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


Aoba Johsai High

  • Tōru Oikawa:
    Oikawa and Iwaizumi have been best friends since childhood, Oikawa dubbing the latter "Iwa-chan". Due to knowing him so long, Iwaizumi is one of the few who is able to tell when Oikawa is genuinely happy and not faking it for show and is able to tolerate his nonsense for the most part. Though Iwaizumi often insults Oikawa (dubbing him "Shittykawa","Trashykawa","Assikawa" , "Crappykawa", "Kusokawa","Lazykawa", "Loserkawa", "Dumbass".) and the two bicker, they work together brilliantly on the court and are completely in sync. Oikawa tends to toss to Iwaizumi if he feels as if he's in a tricky situation. Iwaizumi is often the one to keep Oikawa in check and drag him away from fangirls, much to the latter's dismay. 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. Iwaizumi hates it when Oikawa undermines himself, and angrily reminds him "you're a setter, aren't you!" when Oikawa insists that Kageyama was better at tosses.
  • Takahiro Hanamaki:
    Hanamaki and Iwaizumi seem close, though the former is concerned about beating the latter in arm wrestling. He seems to wish to surpass Iwaizumi in strength. He likes to watch (or even join in with) Oikawa teasing Iwaizumi, or the other way around.


Guys that girls squeal over piss me off even more.
Let's go. It won't matter if we [Aobajōsai] don't win.
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!
Someone who can't see the opponent standing right in front of him, can't defeat the opponent that lies beyond!
Hey. Do what we usually do... Let me take this challenge.
Don't think about anything unnecessary. No matter what, you only need to focus on the ball in front of you.
"How can I be the ace when I couldn't even make that?!"
You're the best partner that I can boast. You're a really amazing setter. Even if the team changes, that will not change. But when we fight, I will defeat you."


  • Favorite food: Agedashi tofu
  • Current concern: "Just 1cm more..or 7mm, at least..!" (In regard to his height.)
  • He is the oldest in Seijō out of all the members whose birthdays have been revealed.
  • He is very athletic as shown by him beating Kyōtani in several events such as running, batting, and arm-wrestling.
  • His star sign is Gemini.
  • When combined, Iwaizumi and Oikawa's first names (Hajime and Tōru respectively) form  "一徹" meaning "obstinate" or "dauntless".
  • 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.
  • It has been confirmed in Chapter 395 of the manga that Iwaizumi and Oikawa are attending different universities.
  • While Iwaizumi is taller than average, he's the shortest of the Seijō 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.[2]
  • 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).
  • He's not very good at drawing.
  • In Haikyuu's first popularity poll, Iwaizumi placed 11th with 3,097 votes.[3] In the second, he rose to 9th with 6,111 votes.[4]
  • Nomenclature:
    • Hajime (一) - One
    • Iwaizumi (岩泉) - Rock (Iwa) Spring/Fountain (Izumi)


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