Osamu Katō was a Japanese voice actor born on January 1, 1936, in Tokyo, Japan. Throughout his career, he was affiliated with several talent management agencies, including Gekidan Izumiza, Theatre Voice Edge, Production M3, and Production Baobab, and he also served as an auditor for the Japan Actors' Union. His career spanned from the 1970s onwards, during which he built a substantial portfolio of roles in anime television series and films.

Katō was a prolific presence in anime of the 1970s and 1980s, particularly in the mecha and superhero genres. He is perhaps best known for his work in the Mazinger series, where he voiced multiple characters. He provided the voice of Duke Gorgon, a recurring antagonist, in both Mazinger Z and its sequel, Great Mazinger. In addition to Duke Gorgon, he also voiced the character Nuke in Great Mazinger. His other notable roles in this era include the warrior beast Doron in Devilman, Pancho in Kotetsu Jeeg, and Yamagatake in Daiku Maryu Gaiking.

Katō also had a long association with the Doraemon franchise. He was the first voice actor to portray the role of Nobita's teacher in the 1973 Nippon Television adaptation of Doraemon. Later, when the series was revived by TV Asahi in 1979, he took on the role of Suneo Honekawa's father, a part he played for many years. His involvement with the series extended to its theatrical films, where he lent his voice to various characters in features such as Doraemon: Nobita's Great Adventure into the Underworld, Doraemon: Nobita and the Steel Troops, and Doraemon: Nobita's Diary on the Creation of the World.

His voice can also be heard in many other classic anime productions. In the Gundam franchise, he appeared as Conscon in Mobile Suit Gundam III: Encounters in Space and as Robert Gomez in Mobile Suit V Gundam. He played Heshi Carmel in the realistic mecha series Fang of the Sun Dougram and Seiichi Tomii in the long-running gourmet series Oishinbo. Other credits include roles in The Yearling, Kōya no Shōnen Isamu, Sugata Sanshiro, and the Anpanman film Soreike! Anpanman: Kirakiraboshi no namida, where he voiced the character Doronko Maou..