Risa Hayamizu is a Japanese voice actress and stage performer born on February 28, 1975, in Osaka Prefecture, Japan. She is affiliated with the talent agency Arts Vision and is recognized for her versatile vocal range, portraying characters across various anime, video games, and theatrical productions.

Hayamizu's path to voice acting began with formal training at the Yoyogi Animation Academy and the Osaka branch of the Japan Narration Acting Institute. Before relocating to Tokyo, she gained performance experience with theater companies in Osaka, including Satsukawaizumi 21, and also appeared in the MBS daytime drama Pure Love. Her professional career was launched after winning the Grand Prize in the Enix Anime Planning Grand Prize voice actor audition in 1998, a competition where her contemporaries included fellow voice actresses Sakura Nogawa and Yui Sakakibara.

Her filmography is extensive, featuring a wide array of supporting and principal roles. She is well-known for voicing Matako Kijima in the long-running series Gintama. Another significant and recurring role is Maria Momoe, the passionate female coach in the baseball anime Big Windup! (Ookiku Furikabutte). In the fantasy action series Basilisk, she provided the voice for the kunoichi Kagerou. Hayamizu also took on the dual role of twins Yū and Aoi Kuchiba in The Qwaser of Stigmata and portrayed Maya Takahashi in the romance series Amagami SS. Her work includes main roles in anime such as Cao Ling Shen in Fighting Beauty Wulong and Saori Eguchi in Mirmo!.

Hayamizu has been a consistent presence in several major franchises. She has voiced multiple characters across the Pretty Rhythm idol series, including Kyōko Asechi and Rabbit-chi. She appeared in the Pokémon franchise as Nozomi in Pokémon Diamond & Pearl and later as Bisces in Pocket Monsters (2019). In the Gundam universe, she played Shin's mother in Gundam Seed Destiny and Linda Vashti in Mobile Suit Gundam 00. Her long list of credits also includes roles in popular series like Skip Beat! as Kanae Kotonami, Daily Lives of High School Boys as Motoharu's older sister, Encouragement of Climb as Mai Aoba, and numerous guest roles in the long-running detective series Case Closed (Detective Conan).

Beyond animation, Hayamizu has contributed her voice to video games, such as Reika in the Dream Club series and Lisa Koizumi in the drama CD and game adaptations of Love Com. She has also been involved in dubbing foreign productions and continues to participate in stage performances, demonstrating her range as a performer. Known for her warm persona and skill with her native Kansai dialect, Hayamizu has maintained a steady and respected career in the Japanese entertainment industry since her debut.