The factor of runoff and sediment changes of the Yangtze River is numerous,and influence from human activities to water and sediment movement is becoming more and more obvious besides natural factors.Runoff and sediment changes of the Yangtze estuary are influenced by natural and human activities.Comparing and analyzing the runoff and sediment discharge of Xuliujing station and Datong station,we know that Datong station can be used as the control station of the Yangtze estuary.Based on the hydrological data of Datong station,this paper analyzes the variation of runoff,sediment discharge and suspended sediment particle size in the the Yangtze estuary during 1950—2011,and obtains the runoff,sediment discharge and sediment diameter of the Yangtze estuary.The results show that there is no trend change of runoff in the Yangtze River basin.After 2003,the Three Gorges reservoir plays a regulating role,and the distribution of runoff during the year shows the decrease in the flood season and the increase in the dry season.Since 1986,the sediment discharge in the Yangtze River basin has been greatly reduced.The seasonal variation proportion generally shows that it’s decreasing in the flood season and increasing in the dry season.After the impoundment of the Three Gorges reservoir in 2003,the sediment discharge has been further reduced and during flood season sediment discharge is decreasing obviously.The average suspended sediment particle size in Datong station is not obvious before and after 2003,and the grain size is slightly coarser from grain size component.