The Jiashen Incident (simplified Chinese: 甲申之变; traditional Chinese: 甲申之變), also known as the Battle of Beijing, took place in 1644 in the areas surrounding Beijing, and was fought between forces of the incumbent Ming dynasty and the Shun dynasty founded by peasant rebel leader Li Zicheng.

Li Zicheng led his rebel army to attack the Ming capital Beijing from two directions (north and south).

The eunuch official Du Zhizhi (杜之秩) ordered the Ming forces defending Beijing to open the city gates and let Li Zicheng's army in.

After the fall of Beijing, the last Ming ruler, the Chongzhen Emperor, committed suicide by hanging himself on a tree in Mount Mei near the Forbidden City.

Li Zicheng's short-lived Shun dynasty would be subsequently defeated by forces of the Manchu-led Qing dynasty, which would go on to rule China proper until its fall in 1912.