Li Longji's father Li Dan is the eighth son of Tang Gaozong, the youngest son of Wu Zetian and the fifth emperor of the Tang Dynasty. In the fourth year of Jinglong (7 10), Zhongzong was poisoned, and Li Longji, the son of Li Dan, joined forces with the court generals to launch a coup and made Li Dan emperor. In the first year of his birth (7 12), Li Dan abdicated as the emperor's father, and Prince Li Longji succeeded him.