Social area analysis is a conventional approach of studying social division and social structure in urban area. However, it mainly focused on the interpretation of demographic indicators, but neglected spatial dimension, thus it is generally difficult to discover the diversity of social space in different cities by such way. Taking the methods of social atlas for reference, this paper primarily attempts to present a series of social maps based on the Sixth National Census and POI data from electronic map. And then, from the characteristics of the maps, an improved index system of social space is brought forward, which includes "demographic properties", "social facilities" and "organization" . With a cluster analysis based on this system, 11 types of social areas are identified in Dongguan, namely (1) old city center, (2) high-rise residential and commercial areas, (3) general residential areas, (4) sub-commercial center, (5) administration center, (6) industrial community areas, (7) low density suburban areas, (8) historical culture areas, (9) new residential areas, (10) agricultural areas, and (11) old age community. Furthermore, it can be concluded into 3 kinds of social space: urban community, rural community, and rural migrant workers community, which demonstrated that Dongguan shows a Triad Spatial Structure model. In the end, this research declares that social atlas is an advanced research method for social space analysis in urban area, as it effectively help to understand the complexity of social space, and reconstruct the research framework of social space in China.