The Battle of Songjin (Chinese: 松錦之戰) was fought in 1641 and 1642 at Songshan (Chinese: 松山) and Jinzhou (Chinese: 锦州), hence the name "Song-Jin". Hong Chengchou's 100,000 elite troops, sent to break the siege of Jinzhou, were crushed by the Eight banner armies of the Qing Dynasty at Songshan. Hong Chengchou and a small number of the remaining troops were besieged at Songshan and defeated a few months later. The Jinzhou garrison and the general Zu Dashou surrendered to the Qing army shortly after the defeat of Ming armies at Songshan.

Since the time of Yuan Chonghuan, the Ming dynasty had rarely changed its Liaodong defensive strategy. Ming leaders largely spent their energies building fortresses, relying on artillery and cannons as defensive measures rather than going on the offensive. For a time this defensive strategy frustrated the Qing army, but eventually Hong Taiji was able to develop a solution for the Qing by reforming their logistical operations, creating supply lines that allowed them to prosecute long-term siege warfare.

Zu Dashou was by then in charge of defense in Jinzhou. Zu had surrendered to Qing at the Battle of Dalinghe and offered to take Jinzhou. When he succeeded taking Jinzhou, he switched sides again and took control of Jinzhou. In the 6th year of Chongde (1641) Jirgalang ordered his troops to retake Jinzhou and lay siege to the city. Zu then sent a letter seeking reinforcements from Beijing. In the fourth lunar month, Hong Taiji decided to maintain the siege upon Jinzhou.

Marshal Hong Chengchou was ordered by the Chongzhen Emperor to rescue Zu Dashou and his army. Under his command, there were 8 area commander in chiefs (Zongbing) and more than 100,000 troops, which included Wu Sangui and Cao Bianjiao's troops.

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