Li Mi (李密) (582–619), courtesy name Xuansui (玄邃), pseudonym Liu Zhiyuan (劉智遠), 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, and Li subsequently led a rebellion against Emperor Yang in his own right in 617. He gained so much following that there was widespread expectation that he soon would be able to 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 forced 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 him.
Li Mi came from a line that was part of the nobility during successive dynasties Western Wei, Northern Zhou, and Sui Dynasty. By the time of his father Li Kuan (李寬), who carried the Sui-created title of Duke of Pushan, the clan, although not originally from there, lived at the Sui capital Chang'an. Due to his father's position, Li Mi became a guard of Emperor Yang of Sui, and he was said to view money lightly, using it to instead gather friends around him. One day, however, when Emperor Yang saw him, Emperor Yang was apprehensive of his appearance, and told his associate Yuwen Shu the Duke of Xu to have Li Mi removed. Thereafter, Yuwen persuaded Li Mi to resign from the imperial guard corps, and Li instead often traveled around the capital, riding a bull and reading while doing so—particularly the Book of Han. When the prime minister Yang Su the Duke of Yue saw him, he was surprised by Li Mi's studiousness, and as Li knew it was the prime minister, he respectfully bowed and stated his name. Yang Su took Li to his mansion and talked with him. Impressed, he told his son Yang Xuangan, "Li Mi's intelligence and capability is far beyond yours." Thereafter, Yang Xuangan and Li Mi became friends. Sometimes, Yang Xuangan would bully Li, and Li responded: