Liu Ji (Chinese: 劉濟; 757 – August 20, 810[1]), courtesy name Jizhi (濟之),[2] was a general of the Chinese Tang dynasty who served as the military governor (jiedushi) of Lulong Circuit (盧龍, headquartered in modern Beijing) from 787 (succeeding his father Liu Peng) to his death in 810, when he was poisoned by his son Liu Zong during an imperially-sanctioned campaign against neighboring Chengde Circuit (成德, headquartered in modern Shijiazhuang, Hebei).