Wu Rui 吳芮 (d. 202 BCE) was one of the regional rulers at the end of the Qin dynasty 秦 (221-206 BCE). He was magistrate (ling 令) of Poyang 鄱陽 during the Qin period and was therefore known as Lord Po 鄱君.
When the first uprisings against the Qin dynasty began, he joined and followed Liu Bang 劉邦 in the conquest of the metropolitan region. Xiang Yu 項羽, the hegemonial king of that time, enreoffed Wu Rui as King of Hengshan 衡山, with the residence in Zhu 邾 (modern Huanggang 黃岡, Hubei). When the war broke out between Liu Bang and Xiang Yu, he immediately declared supporting Liu Bang.
Although never involved in the fightings, he was made King of Changsha 長沙 when Liu Bang proclaimed himself emperor in 202 BCE. Wu Rui died in the same year. He was given the posthumous title of King Wen of Changsha 長沙文王.
His descendants never rebelled against Liu Bang and were the only kings in the empire not related to the imperial house. His successors as kings of Changsha were: Wu Chen 吳臣 (King Cheng 長沙成王, r. 202-194), Wu Hui 吳回 (King Ai 長沙哀王, r. 194-188), Wu Ruo 吳若 (King Gong 長沙共王, r. 188-178) and Wu Chan 吳產 (King Jing 長沙靖王, r. 178-157). Wu Chan had no heir, and the kingdom was as princedom given to Liu Fa 劉發, a son of Emperor Jing 漢景帝 (r. 157-141).