Urban land evolution reflects the law, tendency and contradiction in economic and social development. This paper explains the fundamental theoretical problems of urban land evolution research. And then four features of urban land evolution in Suzhou area are summarized including amount, location structure, function structure and spatial structure features. At last the mechanism of urban land evolution is analyzed. It is pointed out that the decisive factor influencing urban land evolution is economic growth and economic structure in the 1980’s-1990’s in this area.