Taking the 42 districts (county) as the research object in the Chengdu Chongqing urban agglomeration development plan published in 16 years, the urban scale distribution law of Chengdu Chongqing city group is studied by using the method of city first degree, position order scale law and so on. And the data are applied to the data by the mathematical statistics software SPSS. A series of conclusions were obtained by the regression analysis. The results show that the Chengdu Chongqing city group, as the urban agglomeration in the central and western regions, belongs to the typical dual core city of distribution. Chengdu and Chongqing as the two poles of the urban agglomeration attract a large number of population migration, the agglomeration effect of the big cities is obvious, the development of the two poles is good, the urbanization rate is far more than the average level of Sichuan province. The development of other cities in Sichuan is relatively backward, the scale of cities is not large, and there is still a lot of room for development.