Aiming at the problem of sea level rising caused by global warming affects the hydrological characteristics of the estuaries in recent years,we study the impact of sea level rising on the flood and ebb duration difference of the Yangtze River estuary.We apply a two-dimensional mathematical tidal current model to simulate the effect of 100 cm sea level rising on the flood and ebb duration difference of the Yangtze River estuary when the runoff conditions of Datong in the upper reach are flood season,dry season and annual average runoff.The results show that sea level rising reduces the flood and ebb duration difference in the upper and middle reaches of the north branch,the south branch,the north channel and the south channel of the Yangtze River estuary,and has little effect in the last part of the north branch,the north passage and south passage near the offshore area.Sea level rising increases the flood tidal momentum of the estuaries,which reduces the flood and ebb duration difference of the Yangtze River estuary.Therefore,its impact on saltwater intrusion and sediment transport in the Yangtze River estuary must be taken seriously.