Yonehara Kousuke is a Japanese singer and actor. He is part of the J-pop and acting group Run&Gun. He was born in Osaka.

He started his career as a Johnny's Jr. but left the company early to join the dance group DANK which later evolved into Run&Gun.

He is best known for his part in Musical Air Gear. In the first musical he played Team Bacchus' member Hamlet, but in the second installment he took over the role of Romeo from Kamiyama Ryuji after he had replaced Kenta Kamakari (who had fallen ill) as Ikki.

He also played the female role of Rosemary in several Maria Magdalena stages.

Between April 2010 and March 2012, he was the drummer of the ikemen J-rock group ココア男 (Cocoa Otoko).

Currently he mainly does stage acting.