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 Isono (磯野 カツオ), a fictional character in the Sazae-san comic strip
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 Okazaki (岡崎 勝男) (1897–1965), Japanese long-distance runner and politician
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
