Based on the theory of landscape ecology, it analyses the processes of wetland changes in middle-lower reaches of Taoer river between the year of 1986, 1996, 2000, and discusses the characteristic of wetland change in its quantity and wetland landscape pattern's dynamic, the driving forces also. It pointes that wetland represents apparently declining trend in quantity and scope in recently ten years over, with natural wetland's transformation to artificial. Hydrological factor is direct cause of wetland's change, and natural and artificial factors affect it by different intension and manner.