Liu Xun (劉鄩) (858-June 10, 921) was a major general of the Chinese Five Dynasties and Ten Kingdoms period state Later Liang. He was a key commander of Later Liang forces in its struggle with its archenemy Jin, but, after repeated defeats by the Jin prince Li Cunxu, Liu sought retirement, and was subsequently poisoned to death by the Later Liang emperor Zhu Zhen, who doubted his loyalty.
Liu Xun was born in 858, during the reign of Emperor Xuānzong of Tang. His family was from Anqiu (安丘, in modern Weifang, Shandong). His grandfather Liu Shou (劉綬) served as a census administrator for the prefectural government of Mi Prefecture, which Anqiu belonged to, and his father Liu Rong (劉融) served as the Anqiu County magistrate. It was said that Liu Xun was ambitious in his youth, favored the study of military strategies, and studied histories and biographies. Sometime during the Zhonghe era (881-885) era of Emperor Xuānzong's grandson Emperor Xizong, Liu became a low-level officer under Wang Jingwu the military governor of Pinglu Circuit (平盧, headquartered in modern Weifang).
In 889, Wang Jianwu died. The Pinglu soldiers supported his 15-year-old son Wang Shifan to replace him. However, one of his subordinates, Zhang Chan (張蟾) the prefect of Di Prefecture (棣州, in modern Binzhou, Shandong), refused to accept Wang Shifan and requested that then-ruling Emperor Zhaozong (Emperor Xizong's brother and successor) commission a replacement. Emperor Zhaozong thus commissioned the senior official Cui Anqian as the military governor of Pinglu, and Cui went to Di Prefecture to join Zhang in a campaign against Wang Shifan; the sides fought for more than a year. In spring 891, when Wang sent the officer Lu Hong (盧弘) to attack Zhang, Lu instead turned against Wang and prepared to attack him. Wang pretended to be fearful of Lu and offered to surrender the governorship to Lu if Lu would spare him. Lu believed Wang and prepared to return to the Pinglu capital Qing Prefecture (青州) to take over. Wang instead approached Liu Xun, promising to promote him if he could kill Lu; Liu agreed. At a subsequent feast Wang held for Lu upon Lu's arrival, Liu surprised and killed Lu and several of his key followers. Wang then attacked Di himself and killed Zhang; Cui fled back to the imperial capital Chang'an. Emperor Zhaozong then commissioned Wang as full military governor, and Wang made Liu the deputy commander of the Pinglu infantry and cavalry.