Koshiro Sakamoto (坂本 光士郎, Sakamoto Koshiro, born September 9, 1994) is a professional Japanese baseball pitcher for the Chiba Lotte Marines of Nippon Professional Baseball (NPB).

[1][2] He previously played in NPB for the Tokyo Yakult Swallows.

On April 24, 2019, Sakamoto made his NPB debut for the Tokyo Yakult Swallows.

On July 28, 2022, Sakamoto was traded to the Chiba Lotte Marines in exchange for Daiki Yamamoto.

[citation needed] This biographical article relating to a Japanese baseball pitcher is a stub.