The Taira (平) was one of the four most important clans that dominated Japanese politics during the Heian period of Japanese history – the others being the Minamoto, the Fujiwara, and the Tachibana. The clan is divided into four major groups, named after the emperors they descended from: Kanmu Heishi, Ninmyō Heishi, Montoku Heishi, and Kōkō Heishi, the most influential of which was the Kanmu Heishi line.

This is a list of Japanese clans. The old clans (gōzoku) mentioned in the Nihon Shoki and Kojiki lost their political power before the Heian period, during which new aristocracies and families, kuge, emerged in their place. After the Heian period, the samurai warrior clans gradually increased in importance and power until they came to dominate the country after the founding of the first shogunate.