By the contrastive methods, this paper analyzes the change of the channel condition in the upriver and middle reaches of the Yangtze River before and after the impoundment of the TGP, and calculates the shipping cost of the ship route from Chongqing to Yichang, based on the representative ships. It is concluded that the water transportation cost and oil consumption are decreased obviously, and it is suggested to speed up the channel regulation and ship types standardization to improve the traffic capacity of the Three Gorges project.