Gao Heng (Chinese: 高恆; 570–577), often known in history as the Youzhu of Northern Qi ((北)齊幼主), was briefly an emperor of Northern Qi. In 577, with Northern Qi under a major attack by rival Northern Zhou, Gao Heng's father Gao Wei, then emperor, wanted to try to deflect ill omens that portended a change in imperial status, and therefore passed the throne to Gao Heng. Later that year, after they fled in face of Northern Zhou forces' arrival, they were captured and taken to the Northern Zhou capital Chang'an, where, in winter 577, Emperor Wu of Northern Zhou ordered them, as well as other members of the Gao clan, to commit suicide. Northern Qi territory was seized by Northern Zhou, although for several years Gao Wei's cousin Gao Shaoyi claimed imperial title in exile under Tujue's protection.
Gao Heng was born in summer 570, as the oldest son of the emperor Gao Wei. His mother was Gao Wei's then-concubine Consort Mu Sheli. To celebrate his birth, Gao Wei declared a general pardon. Gao Wei's powerful wet nurse Lu Lingxuan, who was also Consort Mu's adoptive mother, wanted Gao Heng to be crown prince and eventually inherit Gao Wei's throne, but was afraid of opposition by Gao Wei's wife Empress Hulü. She therefore, with Gao Wei's approval, gave Gao Heng to Empress Hulü to raise. Later that year, when Gao Heng was only three months old, Gao Wei created him crown prince. After Empress Hulü's father, the general Hulü Guang, was executed under false charges of treason, Empress Hulü was deposed, and while initially Consort Mu was not created empress, in winter 572 she was first created "Right Empress," and then became sole empress in 573 after Left Empress Hu was deposed.