The coup of Cao Mao was a coup d'état that occurred on 2 June 260 in Luoyang, the capital of the state of Cao Wei, during the Three Kingdoms period. Cao Mao, the nominal emperor of Wei, attempted to launch a coup to oust the regent Sima Zhao, who effectively controlled the Wei government. However, the coup concluded with Cao Mao's death and Sima Zhao retaining his status. Contrary to its intention, the coup actually increased the Sima clan's power and influence in Wei, thus providing a foundation for the eventual usurpation of the Wei throne in 266 by Sima Zhao's son Sima Yan, who founded the Western Jin Dynasty.