Based on the 1985, 1992, 1996, 2000 and 2002 statistics of acreages of land under different land use, this paper adopted the structural quantitative analysis method of the landscape ecology in its research on variation of land-use structure in Nanjing from 1985 to 2002. And then driving forces and mechanisms of the variation were analyzed. The results showed: ①this method could reveal law of the variation;②the variation was characterized by: increased diversification, evenness and heterogeneity, which was especially distinct from 2000 to 2002;③the variation was strongly subject to influence of the factors, such as economic development, increasing population, infrastructure construction, industrial restructuring and change in land policy.