The An Shi Rebellion refers to a rebellion against the Tang Dynasty from the fourteenth year of Tianbao during the reign of Emperor Xuanzong to the first year of Baoying under the reign of Daizong (755-762). The "An" and "Shi" refers to An Lushan and Shi Siming respectively.

The military commissioner An Lushan beguiled the trust of Emperor Xuanzong and Li Linfu (Prime Minister). In October, 755, after meticulous preparation, An Lushan launched a rebellion together with Shi Siming against Tang in the name of sending a punitive expedition against Yang Guozhong. As the Tang regime had maintained political stability for a long time and military training had been neglected, An Lushan led the rebellious army from Fanyang southward and captured the east capital Luoyang within two months. The next year he entitled himself the Emperor of Dayan and his regime "Yan".

This historical event was triggered by various social contradictions and exerted great influence upon the late Tang Dynasty. It was the turning point of the dynasty from prosperity to decline.