Starting from trend of public land revenue and urban land scale, this thesis analyzes land revenue, supply-demand of urban land, and sets up a regression model on urban land expansion by using provincial panel data (2000-2010) in China. This model tests data of whole country, east, middle and west of China. The results indicate that: (1) land taxes exhibit their obvious positive incentive on urban land expansion, but, land market revenues show the diversity because of different revenue types. (2) land demand appears stronger initiative than supply as a motive force of urban land expansion. (3) Effects of each factor on urban expansion have large differences in the east, middle and west.