|“||Someone who can't see the opponent standing right in front of him, can't defeat the opponent that lies beyond!||”|
|Also Known As||Iwa-chan (By Oikawa)|
|Date of Birth||June 10|
|Height||179.3 cm (5' 10.6")|
|Weight||70.2 kg (154.7 lbs)|
|Likes|| Volleyball |
|Occupation|| High School Student |
(3rd Year, Class 5)
|Teams|| Kitagawa Daiichi Junior High (former)|
|Position|| Wing Spiker |
|In the Manga||A "Reunion" and "Utter Failure"|
|In the Anime||An Interesting Team|
|Voice Actor||Yoshino Hiroyuki|
Hajime Iwaizumi (Japanese: 岩泉一 Iwaizumi Hajime) is a third-year student from Aobajōsai High; he is the volleyball team's ace, vice captain and a wing spiker. He is also Tōru Oikawa's childhood friend and "pillar".
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 Aobajōsai uniform with number four on it. He is otherwise shown wearing an Aobajōsai school uniform consisting of khakis with dark brown details, a lavender-coloured button down shirt, a dark red tie, and a white blazer. Iwaizumi's uniform appears to be missing the cream-coloured vest that goes with the rest of the uniform and appears to be slightly dishevelled, with his tie loose around his neck and his shirt left untucked.
Iwaizumi is a stubborn but reliable teammate, often filling in Oikawa's spot as a morale booster if needed. He acts supportively 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 lead some members of the Aobajōsai team to look up to and respect him.
Iwaizumi is Aobajōsai'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 as gotten older he's grateful that he knows the "thrill" of receiving his opponents' flawless hits (Chapter 144). 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.
- Favorite food: Agedashi tofu
- Current concern: "Just 1cm more..or 7mm, at least..!" (In regard to his height.)
- In the second popularity poll, he was voted 9th with 6111 votes.
- 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 birth date 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 implied in the Seijō extra that Iwaizumi and Oikawa might be attending different universities, although the phrasing is vague enough it's unclear. Furudate has yet to explicitly state whether they will be attending the same school.
- 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).
- 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 afterwards (when asked, he said cicadas had short lifespan so he took pity on them).
- Hajime (一) - One
- Iwaizumi (岩泉) - Rock (Iwa) Spring/Fountain (izumi)