The Ryūzōji clan (龍造寺氏 Ryūzōji-shi) was a Japanese clan which claimed descent from Fujiwara Hidesato. It came to prominence in the Sengoku period, in the fighting in northern Kyūshū. Their descendants became retainers of the Matsudaira clan of Aizu, and remained there until the Meiji Restoration. The clan was cornered, huddled away into the South-west corner of Japan, with Ōtomo to the east and Shimazu to the south.