Isamu Yūsen is a Japanese voice actor born on January 10, 1982, in Osaka, Japan. His career encompasses a wide range of roles in anime television series, animated films, and video games.

Yūsen has built an extensive filmography in anime, with many of his credits spanning the 2010s and 2020s. He is perhaps best known for his recurring roles in the popular sports anime Haikyuu!!, where he voiced both Issei Matsukawa and Yutaka Obara across multiple seasons and a film adaptation. His other notable anime roles include Sakai in JoJo's Bizarre Adventure: Diamond is Unbreakable, Yoshinori Iwakuma in Welcome to the Ballroom, and Kazuya Suou in Smile Down the Runway. More recently, his work includes the role of the King of Fortna in Nina the Starry Bride and a veterinarian in Kinokoinu: Mushroom Pup.

Beyond television, Yūsen's voice work extends to anime films and original net animations. His film credits include Haikyuu!! the Movie: The Winner and the Loser, and he provided a voice for the 2022 web series Vampire in the Garden. In addition to anime, he has performed voice roles in video games and live-action series, including the English-dubbed version of the survival game Days Gone and the tokusatsu series Ultraman X.