Haruhiro Hamaguchi (濵口 遥大, Hamaguchi Haruhiro, born March 16, 1995) is a professional Japanese baseball player.

He plays pitcher for the Fukuoka SoftBank Hawks.

In Game 4 of the 2017 Japan Series, with DeNA facing elimination, Hamaguchi did not allow a hit for 7+1⁄3 innings.

[1] On October 10, 2018, he was selected Japan national baseball team at the 2018 MLB Japan All-Star Series.

This biographical article relating to a Japanese baseball pitcher is a stub.