Hall of mental cultivation was built in the Jiajing period of Ming Dynasty, located on the west side of Gan Qing Palace in the Imperial Palace. The emperor shunzhi died here in the early Qing Dynasty. During the reign of Emperor Kangxi, it was once used as a workshop for the palace office, specializing in the production of palace supplies. Since Yong Zhengdi moved into hall of mental cultivation, the workshops built by him have gradually moved out of the palace and have been used as the palace of the Qing Dynasty. During the Qianlong period, it was rebuilt and built, becoming a multi-functional building complex integrating ministers, handling government affairs, and studying, studying and living for the emperor. Before Puyi left the palace, eight emperors in Qing Dynasty lived in hall of mental cultivation.