Considering the interaction between the Yangtze waterway transport and the ecological environment,the carrying capacity concept of resources and environment discipline is introduced,and the connotation of carrying capacity of water transportation of the Yangtze waterway is defined.The algorithm of carrying capacity of water transportation of the Yangtze waterway is constructed,which is related to many factors such as freight volume,waterway capacity,shipping density and ship pollutant discharge.Based on the premise that the total amount of pollutants discharged from ships does not increase,the carrying capacity of the Yangtze waterway in 2035 is obtained.The conclusion shows that if the environmental capacity is allowed to increase moderately,or the transportation organization is further optimized,the technical performance of ships is improved,clean energy is widely applied in ship，and pollutant discharge is controlled,there is still a large space for improving the water transport capacity of the Yangtze waterway.