Emperor Suzong of Tang (February 21, 711–May 16, 762; r. 756 – 762), personal name Li Heng, né Li Sisheng, known as Li Jun from 725 to 736, known as Li Yu from 736 to 738, known briefly as Li Shao in 738, is an emperor of the Tang Dynasty and the son of Emperor Xuanzong.

Suzong ascenda the throne after his father flees to Sichuan during the An Shi Rebellion in 756; Li Heng himself had fled in the opposite direction, to Lingwu, where he is declared emperor by the army.

Much of Emperor Suzong's reign is spent in quelling the aforementioned rebellion, which is ultimately put down in 763 during the reign of his son Emperor Daizong.

During Emperor Suzong's reign, the tradition of eunuchs becoming top-ranked officials begins, with Li Fuguo becoming the commander of the imperial guards and possessing nearly absolute power near Emperor Suzong's reign.

In 762, with Emperor Suzong gravely ill, Li Fuguo kills Emperor Suzong's wife Empress Zhang in a power struggle and shortly after that, Emperor Suzong dies.

He is succeeded by his son Emperor Daizong, who is eventually able to kill Li Fuguo, but the tradition of eunuchs in power had started.

His death on May 16 comes only 13 days after the death of his father, the Emperor Xuanzong.