Saku Mizuno is a Japanese voice actress born on September 29, 1999. She is affiliated with the talent agency Sony Music Artists. Mizuno's path to voice acting began in her childhood, inspired by a desire to perform the special moves she saw in the anime Inazuma Eleven. In 2016, during her second year of high school, she participated in the fifth Anistoteles audition, hosted by Sony Music Artists, which led to her signing with the agency. She made her entertainment debut in 2018.

Mizuno's first main role in an anime television series came in 2021, when she was cast as Rena Hananoi in Selection Project. This was followed by a series of significant roles in 2022 that raised her profile. She voiced the stoic and eccentric bassist Ryo Yamada in the critically acclaimed series Bocchi the Rock! and portrayed Liu Shouxue, the mysterious Raven Consort, in Raven of the Inner Palace. In 2025, she is scheduled to voice the character Amelia Rosequartz in the anime adaptation of My Status as an Assassin Obviously Exceeds the Hero's.

Beyond anime, Mizuno has lent her voice to characters in video games. Her game credits include Akira Hirose in Baton Relay in 2020 and Vivian Banshee in the 2024 title Zenless Zone Zero. She is also a member of Seiyū E-Sports-bu, a group of voice actors who participate in gaming-related activities.

Mizuno is often recognized for her cool and understated vocal delivery, which makes her well-suited for portraying introverted or stoic characters.