The Battle of Suiyang (睢陽之戰) was a battle in Suiyang during the An Shi Rebellion, between the rebel An Lushan's Yan army and the loyalist forces of the Chinese Tang army. Although the battle was ultimately won by Yan, it suffered a major loss of manpower and time. The battle was noted for Tang army's determination to fight to the last man, and also due to the cannibalism that occurred during the siege.