Murong Long (慕容隆) (died 397), formally Prince Kang of Gaoyang (高陽康王), was a general and imperial prince of the Chinese/Xianbei state Later Yan. He was a son of the founding emperor Murong Chui (Emperor Wucheng) and a brother of Murong Bao (Emperor Huimin), and when his brother's empire was under threat from the rival Northern Wei's prince Tuoba Gui, he tried to save it, but was killed by his nephew Murong Hui, intent on seizing power from both his father and his uncles.
The first reference to Murong Long in history was in 369, when Murong Chui, then a Former Yan prince, fled to Former Qin after he came after suspicion of the emperor Murong Wei's mother Empress Dowager Kezuhun and the regent Murong Ping; Murong Long was one of his sons who fled with him. When Murong Chui subsequently resolved to rebel against Former Qin after its emperor Fu Jiān was defeated at the Battle of Fei River in his attempt to conquer Jin and reunite China, Murong Long was involved in his first act of rebellion — massacring the Di soldiers that Murong Chui's deputy, Fu Feilong (苻飛龍), commanded. Murong Chui subsequently declared the independence of Later Yan in 384.
Throughout the next few years, Murong Long largely served as a general directly under his father's command, as Later Yan tried to establish itself over the old territory of Former Yan. In 384, when Murong Chui was nearly trapped by an ambush by the Former Qin viceroy Fu Pi, Murong Long was the one who rescued him from the encounter. In 386, Murong Chui created him the Prince of Gaoyang. He continued to distinguish himself in campaigns against independent warlords and Jin generals. In 389, when his brother Murong Nong, himself a distinguished general, was recalled from his post as viceroy at the old Former Yan capital Longcheng (龍城, in modern Jinzhou, Liaoning), Murong Long replaced him as viceroy, and he followed Murong Nong's policies. The populace favored him as much as Murong Nong.