The Battle of Yan Province was fought between the warlords Cao Cao and Lü Bu for control of Yan Province (covering present-day southwestern Shandong and eastern Henan) in the late Eastern Han dynasty.

Liu Dai, Inspector of Yan Province, wanted to attack the rebels but Bao Xin, Chancellor of Jibei, advised him against it.

Liu Dai ignored Bao Xin's warning, engaged the rebels in battle, and was eventually defeated and killed.

Cao reorganized the surrendered troops to form the Qingzhou Corps (青州兵), while implementing the tuntian system for the people to provide for themselves and the military.

Lü Bu arrived and was unable to take Juancheng by siege so he went west and garrisoned Puyang.

Lü Bu had also used up all his provisions, horse feed, and grain supplies so both sides were forced to withdraw.

Lü Bu then fled eastwards to join Liu Bei, who had taken over Xu Province from Tao Qian.

In 195, Lü Bu turned against Liu Bei, who had offered him refuge in Xu and led to the subsequent Battle of Xiapi in 199, when the allied forces of Cao Cao and Liu Bei launched an attack on Lü Bu in Xu Province.

It should not be confused with the "Battle of Yan Province", which deals with remnants of the Yellow Turban rebels.