【摘要】Empirical analysis and comparative research have been made in this essay on the development scale of the cities in our country.With the analysis on scale efficiency,sustainable development capacity and city size distribution,we conclude that the most efficient and sustainable is those cities with population from 0.5 million to 2 million.Therefore the most important thing about city development is to improve the efficiency and sustainable development capacity of cities under 0.5 million.Our cities still belong to sub rank size disttibu,hence,consequently,we should develop potential big cities beside towns so as to make every size cities distribute reasonably and promote the urbanization of oue country.