Abstract: 1644 was a very important year in Chinese history.LI Zicheng’s Da shun troops were finally defeated by the Qing armies after some battles,and the Qing armies began to dominate the central plains.Besides the deficiency of Li Zicheng’s upper class political quality and their improper strategy,their failure had something to do with their paring no attention to the wing of Hongyi Cannons——style arms on the traditional fighting method especially the HongYi cannons’ large——scale’s making up and using in the battle ground.