Katsuo (written: 勝男, 勝夫, 勝雄 or 嘉葎雄) is a masculine Japanese given name. Notable people with the name include:

• Katsuo Bai (梅 勝夫, born 1940), Japanese basketball player
• Katsuo Haga (芳賀 勝男, born 1938), Japanese boxer
• Katsuo Kameoka (亀岡 勝雄, 1905–?), Japanese boxer
• Katsuo Kanda (神田 勝夫, born 1966), Japanese footballer
• Kiyokuni Katsuo (清國 勝雄, born 1941), Japanese sumo wrestler
• Katsuo Nakamura (中村 嘉葎雄, born 1938), Japanese actor
• Katsuo Nishida (西田 勝男, born 1929), Japanese long-distance runner
• Katsuo Okazaki (岡崎 勝男, 1897–1965), Japanese long-distance runner and politician
• Katsuo Osugi (大杉 勝男, 1945–1992), Japanese baseball player
• Katsuo Takaishi (高石 勝男, 1906–1966), Japanese swimmer
• Katsuo Tokashiki (渡嘉敷 勝男, born 1960), Japanese boxer
• Yutakayama Katsuo (豊山 勝男, born 1937), Japanese sumo wrestler
• Cleyton Katsuo (クレイトンカツオ, born 1988), Brazilian woodworker and developer
• Katsuo Yakura (矢倉克夫), Japanese politician

Fictional characters

• Katsuo Isono (磯野 カツオ), a character in the manga series Sazae-san

See also

• Katsuo, Japanese name for Skipjack tuna and occasionally its substitute bonito
• Katsuō-ji, a Buddhist temple in Osaka Prefecture, Japan