Abstract: This paper attempts to analyze the distribution of the social stratum based on the data of the 6th census of population,and found that the social space of Beijing differentiates into 3 belts of the core,the semi-periphery and the periphery.On the view of districts,Beijing is a mixed social space besides the remote districts in rural areas.The social segregation appears as the whole mixed situation of the closed residential area and the squatter settlements and old areas surrounded it.The social segregation between urban and rural is bigger than the social segregation among the urban areas.