Digunai, also known by his sinicised name Wanyan Liang and his formal title Prince of Hailing, was the fourth emperor of the Jurchen-led Jin dynasty of China. He was the second son of Wanyan Zonggan, the eldest son of the dynastic founder Wanyan Aguda. He came to power in 1150 after overthrowing and murdering his predecessor, Emperor Xizong, in a coup d'état. During his reign, he moved the Jin capital from Shangjing to Yanjing, and introduced a policy of sinicisation. In 1161, after the Jin dynasty lost the Battle of Caishi against the Southern Song dynasty, Digunai's subordinates rebelled against him and assassinated him. After his death, even though he ruled as an emperor during his lifetime, he was posthumously demoted to the status of a prince – "Prince Yang of Hailing" (海陵煬王) – in 1162 by his successor, Emperor Shizong. However, in 1181, Emperor Shizong further posthumously demoted him to the status of a commoner, hence he is also known as the "Commoner of Hailing" (海陵庶人).

The Jin dynasty, officially known as the Great Jin, was an imperial dynasty of China that existed between 1115 and 1234. Because the Wanyan clan that founded the dynasty were of Jurchen descent, it is also sometimes called the Jurchen dynasty or the Jurchen Jin.