The regulation structure’s surface maintenance in Yibin to Chongqing section of the Yangtze river is affected by unsteady flow caused by hydropower stations in the Jinsha River and Minjiang River.Based on the hourly water level data of Lizhuang station and Zhutuo station in recent years,we analyze the characteristics of the water level change of two stations.The best time of regulation structure surface maintenance in Yibin to Hejiang section and Hejiang to Chongqing section of the Yangtze River is put forward.In order to ensure the quality of structure surface,the thickness of regulation structure surface could be decreased,or section construction could be adopted.