Kusha-shū(倶舎宗?) was one of the 6 Japanese Buddhism schools (Nanto Rokushū(南都六宗?)), introduced to Japan during Asuka and Nara period. Along with Jōjitsu and Ritsu, it was initially based on Nikaya schools, sometimes known derisively as Hinayana. Kusha was never considered to be an independent school. It was considered to be an adjunct of the Hossō sect, due to the main works of both schools being ascribed to Vasubandhu.
Buddhism was introduced into Japan from China. The school takes its name from its authoritative text, Dharma Analysis Treasury, the Abidatsuma-kusha-ron (Sanskrit : Abhidharma-kosa-sastra), by the 4th or 5th century Indian philosopher Vasubandhu. The Kusha school is considered to be an offshoot of the Indian Sarvastivada school.
Names commonly associated with Kusha-shū are Dōshō (道昭 638-700), Joe (644-714), Chitsū (智通 ?-?), Chitatsu (智達 ?-?), and Genbō (玄昉 ?-746). Its teachings were commonly thought to be part of the Hossō sect.