Kōshirō, Koshiro or Koushirou (written: 幸四郎, 孝四郎, 高志郎, 庚子郎 or 公志郎) is a masculine Japanese given name. Notable people with the name include:
Matsumoto Kōshirō (松本 幸四郎), various kabuki actors
Kōshirō Onchi (恩地 孝四郎, 1891–1955), Japanese printmaker and photographer
Koshiro Shimada (島田 高志郎, born 2001), Japanese figure skater
Koshiro Take (武 幸四郎, born 1978), Japanese jockey
Koshiro Ueki (植木 庚子郎, 1900–1980), Japanese politician
Koshiro Yamamuro (山室 公志郎, born 1987), Japanese baseball player
Fictional characters:
Koushiro Izumi (Izzy Izumi in English dub), a fictional character from Digimon Adventure.
Koushiro Sasaki, a fictional character from Machine Robo Rescue.
Koshirō or Koshirou (written: 古志郎) is a separate given name, though it may be romanized the same way:
Koshirō Oikawa (及川 古志郎) (1883–1958), Imperial Japanese Navy admiral
