With the construction of cascade hubs in the lower reaches of the Jinsha River to store water，the navigation of the Jinsha River has become one of the most active inland water transport regions in Sichuan province. Taking the steel products and phosphate bulk cargo in the hinterland of the lower reaches of the Jinsha River as an example，economic of cargo transportation in the hinterland of the lower reaches of the Jinsha River is researched.Combined with the current situation and development trend of comprehensive transportation in hinterland，the reasonable transportation mode and path of steel products and phosphate ore are analyzed，and the method of minimum comprehensive freight is adopted to compare freight rates.It is found that：1） It is more economical to transport steel products，phosphate ore and other water suitable goods in the hinterland of the lower reaches of the Jinsha River. 2） Water suitable goods sold to Yichang，Hubei，and the middle and lower reaches of the Yangtze River should be transferred in the water of Yibin Port. 3） Promoting the construction of cascade navigation structures in Xiluodu，Baihetan and Wudongde is of great significance to give full play to the advantages of navigation in the lower reaches of Jinsha River.