Li Mi (Chinese: 李密; 582 – 20 January 619[1]), courtesy name Xuansui (玄邃), pseudonym Liu Zhiyuan (劉智遠), was a Chinese military general, monarch, poet, politician, and rebel. He was the leader of a rebel movement against the rule of the Chinese Sui dynasty. He initially was the strategist of the Sui general Yang Xuangan, who rebelled against Emperor Yang of Sui in 613 but failed. In 617, Li subsequently led a rebellion against Emperor Yang in his own right and killed Zhai Rang, seizing Zhai's troops.
There was expectation that Li Mi would prevail over Sui forces and establish a new dynasty—so much so that even other key rebel leaders, including Dou Jiande, Meng Haigong (孟海公), Xu Yuanlang, and Zhu Can, were urging him to take imperial title. Even Li Yuan (soon to become the founder of the Tang dynasty as Emperor Gaozu) was writing him in supplicating terms that implicitly supported his imperial claim.
Li Mi tried to gain control of the Sui eastern capital Luoyang, but his forces became stalemated by the Sui forces there, and he never came around to claiming the imperial title, instead accepting the title of Duke of Wei.
In October 618, the Sui general Wang Shichong crushed his forces at Yanshi. Li Mi fled to Tang territory and submitted to Emperor Gaozu, but subsequently rebelled against Tang and tried to revive his own army. The Tang general Sheng Yanshi (盛彥師) captured and executed Li Mi.