Information entropy can be used as a measurement for orderliness of land use structure. Based on the data collected, change in information entropy of the land use structure in the city of Kunshan was analyzed. The information entropy of the land use structure in Kunshan has been rising in general since 1994, indicating decrease in orderliness of the land use system. In terms of space, land use structure differs from district to district in Kunshan:the information entropy of the land use structure in the City Proper and its suburbs is the highest, those in the industry region in the center and the tourist scenic region in the north follow and that in the tourist scenic region in the south is the lowest. The information entropy of land use structure varies significantly with the town. Motivating factors of the variation were also analyzed, and the following conclusions were reached:the information entropy of land use structure is obviously under the influence of economic development, population growth, urbanization, industrialization and economic policies. Economic factors are the most closely related to the information entropy of land use structure, then followed by population growth, industrialization and urbanization in a decreasing order.