Abstract: The potato as the traditional dominant crop of Siziwang Banner, it plays an important role in agricultural product and increasing of farmers’ income in local area. The paper which based on the review of the theory of comparative advantage, used the targets in production scale advantages and indicators of productivity advantages and comprehensive quantitative evaluation of the comparative advantages of index system, reviewed the comparative advantage of the potato industry in Siziwang Banner. The results showed that the production of a comprehensive comparative advantage and comparative scale advantages were obvious in potato industry Siziwangqi Banner, but there was no sustained growth, and the advantages of index down there, which had a great relationship with this mode of operation and production behind, asymmetric information, marketing difficult, potato processing capacity backwardness, low value-added products unfavorable factors. For this, the writer proposed that the local should change the mode of operation, change in marketing concepts, improve value-added products to promote the development of the potato industry.