Mikio (written: 幹夫,幹男, 幹雄, 幹郎, 巳喜男, 三樹夫, 三喜夫, みきお in hiragana or ミキオ in katakana) is a masculine Japanese given name. Notable people with the name include:
Mikio Aoki (青木 幹雄) (born 1934), Japanese politician
Mikio Fujita (藤田 幹雄) (born 1968), Japanese politician
Mikio Hasemoto (1916–1943), American soldier and Medal of Honor recipient
Mikio Igarashi (五十嵐 三喜夫) (born 1955), Japanese manga artist
Mikio Manaka (眞中 幹夫) (born 1969), Japanese footballer
Mikio Narita (成田 三樹夫) (1935–1990), Japanese actor
Mikio Naruse (成瀬 巳喜男) (1905–1969), Japanese film director, screenwriter and producer
Mikio Oda (織田 幹雄) (1905–1998), Japanese athlete
Mikio Sakai (酒井 ミキオ) (born 1970), Japanese singer-songwriter
Mikio Sasaki (佐々木 幹夫) (born 1937), Japanese chief executive
Mikio Sato (佐藤 幹夫) (born 1928), Japanese mathematician
Mikio Shimoji (下地 幹郎) (born 1961), Japanese politician
Mikio Shirai (白井 幹夫) (born 1950), Japanese keyboardist
Mikio Yamamoto (born 1944), Japanese scientist
