The Ōbaku-shū (黄檗宗) is one of three main schools of Zen in Japanese Buddhism, in addition to Sōtō and Rinzai. It had a strong influence on Japanese Rinzai, which partly adopted Ōbaku-practices, and partly reinstored older practices in response to the Ōbaku-school.

Zen is a school of Mahayana Buddhism that originated in China during the Tang dynasty as the Chan School or the Buddha-mind school, and later developed into various sub-schools and branches. From China, Chán spread south to Vietnam and became Vietnamese Thiền, northeast to Korea to become Seon Buddhism, and east to Japan, becoming Japanese Zen.