Ryuunosuke Tanaka

Height: 177.2→178.2 cm / Weight: 68.8 kg / Highest jump reach: 322→324 cm / Birthday: March 3 / Favorite food: Melon bread / Recent concern: Tried to show a seemingly lost first-year girl around the school but ended up making her cry

Second-year WS at Karasuno High School. His jersey number is 5.

His sister Saeko is an alumna of the same school.

Expected to be the "next ace," he is a power spiker who, contrary to his expression and tone, plays with a broad perspective, excelling in blocking out and varying his spike courses. Always the team's mood maker, he provides appropriate support to his teammates and maintains high spirits even under pressure, delivering game-saving spikes time and again with his indomitable spirit. Under the motto "If you keep at it, you can do it," he mastered the super inner cross spike of Koutarou Bokuto from Fukurodani, which he had aimed to learn since the Tokyo training camp, and completed it during the Spring High Tournament.

In live commentary and news programs during the Spring High Tournament, he is highly praised as the "undercover ace" and "charge captain."

With a buzz cut and rough manner of speaking, he might seem like a delinquent at first glance, but he is deeply loyal and respects hierarchy. He has been looking out for Hinata and Kageyama since they joined the club, and was concerned about Tsukishima before the Spring High preliminaries. He also asked his sister (Saeko) to take Hinata and Kageyama, who were in danger of failing, to the joint training camp (Nekoma High School: Tokyo). On the other hand, he does not hide his hostility towards popular boys with girls, opposing players who confront his teammates, and boys who try to approach Kiyoko. Whether intentional or not, he often intimidates opponents, and is sometimes scolded by Sawamura and Sugawara.

Initially had blonde hair and a rough demeanor upon entering high school, but after recognizing three second-year students (then first-years) as "some strong guys," he shaved his head as a sign of renewed determination and has maintained it ever since.

Treated as the noisy second-year duo with Nishinoya, both of them adore manager Kiyoko. He fell in love with Kiyoko at first sight on the first day of joining the club, proposing with "Please marry me" at their first meeting (she declined), and has been happily ignored by her ever since. After graduating from Karasuno High School, he became a sports instructor and is married to Kiyoko.

Like Nishinoya, he struggles with studies. He was tutored by Ennoshita and barely passed the final term exams by avoiding failing grades.