Ryo Kase (加瀬 亮, Kase Ryō, born November 9, 1974 in Yokohama) is a Japanese actor.

Early life
Kase was born in Yokohama, Kanagawa prefecture. He moved to Bellevue, Washington in the United States soon after his birth, due to his father's job being transferred. He's father Yutaka Kase was former chairman and representative director of Sojitz, a Japanese general trading company.

Career
Kase made his screen debut in Sogo Ishii's Gojoe: Spirit War Chronicle in 2000.

He starred in Masayuki Suo's 2007 film I Just Didn't Do It.

International films
He has also appeared in films such as Clint Eastwood's Letters from Iwo Jima, Michel Gondry's Tokyo!, Gus Van Sant's Restless, Abbas Kiarostami's Like Someone in Love, Hong Sang-soo's Hill of Freedom, Takeshi Kitano's Outrage,/ Outrage Beyond, Martin Scorsese's Silence and Paul Weitz's Bel Canto.