Pinglu Canal connects Beibu Gulf Port outward and the Pearl River inward，which is a new waterway that connects the sea and the river.The construction of Pinglu Canal will have a profound impact on the transportation pattern of access to the sea in southwest China.This paper comprehensively analyzes the overall pattern of the current freight transportation corridors to the sea in Southwest China.Then，the comprehensive transportation cost comparison between Pinglu Canal-Beibu Gulf Port river-sea combined transport corridor and the existing southeastward，eastward and southward corridors to the sea is made.It is proposed that Pinglu Canal will mainly have impact on Guangxi，Yunnan and Guizhou Province and affect Chongqing and Sichuan Province indirectly.The construction of Pinglu Canal will bring about the optimization of the freight transport mode and the flow direction to the sea in the southwest China，increase the proportion of southward corridor and enhance the comprehensive competitiveness of the port group around Beibu Gulf.The results can provide decision-making reference for the southwest region to improve the logistics system in advance around the construction of Pinglu Canal