By taking LandSat TM remote sense images in 1986, 1995, 2004, 2007, 2010 and 2014 as data sources, based on using GIS technology to extract urban land of the main city of Chongqing, this paper uses spatial overlay technique to make direction division of urban land expansion of the main city of Chongqing, and by selecting urban expansion index, expansion centroid migration model, compact, fractal dimension, elastic coefficient as the research methods, systematically analyzes temporal and spatial characteristics of urban land expansion of the main city of Chongqing. The results show that in recent nearly 30 years, the urban land of the main city of Chongqing increased 527 km2, yearly average expansion rate reached 18.82 km2, that the expansion area in the north, the west and the northwest is bigger, that the expansion area in southeast is smaller, and that the coordinate of the urban center of the city shifts to the north. Limited by natural condition, the urban land expansion shows a group type but noncompact form. In the future, the expansion of the urban land should pay more attention to the internal filling. The research results are helpful to know the feature of temporal and spatial change of urban land of the main city of Chongqing and provide reference for urban plan and sustainable development of the main city of Chongqing.