Katsuji Mori is a Japanese voice actor and narrator from Tokyo, born on July 10, 1945. Early in his career, he performed under the stage name Setsuya Tanaka. As Setsuya Tanaka, he provided the voice for the protagonist Go Mifune in the classic racing anime Speed Racer, known in Japan as Mach GoGoGo. During this same period under the Tanaka name, he also voiced Joe Shimamura, the lead character designated Cyborg 009, in the 1960s anime adaptation of Cyborg 009.

Beyond these iconic early roles, Mori has a long and varied career with several other notable anime performances. He is widely recognized for voicing Ken the Eagle, the leader of the heroic ninja team in Science Ninja Team Gatchaman. His other significant roles include Garma Zabi in the seminal mecha series Mobile Suit Gundam, Jouji Minami in Tekkaman: The Space Knight, and Nephrite in the first season of the magical girl series Sailor Moon. His filmography also includes parts in series such as Fist of the North Star and Ace wo Nerae.

He has had recurring collaborations with several major anime production studios and franchises. His work on Tatsunoko Productions series is notable, having leading roles in both Gatchaman and its 1990s sequel series, as well as Tekkaman. He also performed roles in the extensive franchise histories of Mobile Suit Gundam and Dragon Ball, where he voiced the characters Pamput and Nail. In addition to his performing career, he operates the voice talent agency Office Mori. While his most famous roles are from the 1960s through the 1980s, he has continued voice work in the 21st century, including reprising the role of Ken the Eagle in the 2013 and 2015 series Gatchaman Crowds.