Using the relative data from 8 modern service industries in 11 provinces of the Yangtze River Economic Belt from 2000 to 2015，this paper measured the spatial agglomeration level of the modern service industry from the perspective of an industry and a region by Ellison-Glaeser index and the average concentration rate method.Based on the Moran index I test for the spatial correlation of modern service industry agglomeration，this article established a spatial fixed model to verify and analyze the factors affecting the concentration of modern service industry.Research shows that the leasing industry and business service industry are the most concentrated in the Yangtze River Economic Belt and the lowest agglomeration is the real estate industry.Shanghai's modern service industry has the highest level of concentration and Guizhou's is the lowest.Government intervention has an inhibitory effect on the average concentration rate of modern service industry in the Yangtze River Economic Belt.Infrastructure，science and technology levels have a positive effect，however，the level of informationization is uncertain about its impact.