Emperor Suzong of Tang, personal name Li Heng, né Li Sisheng (李嗣升), known as Li Jun (李浚) from 725 to 736, known as Li Yu (李璵) from 736 to 738, known briefly as Li Shao (李紹) in 738, was an emperor of the Chinese Tang dynasty and the son of Emperor Xuanzong.

Throughout Chinese history, "Emperor" was the superlative title held by the monarchs who ruled various imperial dynasties. In traditional Chinese political theory, the emperor was the "Son of Heaven", an autocrat with the divine mandate right to rule all under Heaven. Emperors were worshiped posthumously under an imperial cult. The lineage of emperors descended from a paternal family line constituted a dynasty, and succession in most cases theoretically followed agnatic primogeniture.