Hisashi Katsuta was a Japanese actor and voice actor born on April 2, 1927, in Tokyo. He is regarded as a pioneer in the voice acting industry in Japan, with a career that began in the late 1940s and spanned over seven decades until his death on February 21, 2020, at the age of 92.

Katsuta's career originated in radio drama, making his voice acting debut in 1948 with an NHK radio adaptation of the novel Water Margin. He was among the first freelance voice actors in Japan and expanded into dubbing foreign television dramas in 1957, citing series like Surfside 6 and The Beverly Hillbillies as memorable works.

He is best known for his long-standing association with the character Dr. Ochanomizu in the Astro Boy franchise. He first voiced the role in the 1963 anime adaptation and reprised it for the 1980 and 2003 series, as well as in films such as Astro Boy: Hero of Space, Astro Boy: Shinsen-gumi, and the special Tezuka Osamu ga Kieta?! 20 Seiki Saigo no Kaijiken. This role is widely considered his magnum opus.

Throughout his career, Katsuta frequently portrayed wise mentor figures, doctors, and professors. His filmography includes numerous other notable roles. He voiced Dr. Hoshi in Astroganger (1972-1973) and Professor Tobishima in Groizer X (1976-1977). He played Shin'ichirō Izumi, also credited as Professor Izumi, in Tōshō Daimos (1978-1979). In 1979, he voiced Dr. Nasenkopf in the special Undersea Super Train: Marine Express and King Louis XV in The Rose of Versailles. He also took on minor roles in a wide range of series, including Voltes V, Cat's Eye, Dororo, Jetter Mars, Kimba the White Lion, Legend of the Galactic Heroes, Megazone 23, and Oishinbo.

Beyond performance, Katsuta made significant contributions to the voice acting profession as an educator and author. In 1982, he founded a voice acting class that later became the Katsuta Voice Acting Academy in 1987, where he served as dean and mentored new generations of talent until its closure in 2015. He also authored books on the subject, including an autobiography and a volume profiling influential voice actors. In recognition of his lifetime achievements and pioneering work, he was a recipient of the Synergy Award at the 3rd Seiyu Awards in 2009.