Abstract: The Ebinur Lake of Xinjiang is a typical closed inland lake located in the arid region of northwestern China. Because of the arid climate and human activity, the lake area changed dramatically in the past decades. Lake area shrinkage caused by the ecological environment deterioration has become important restraining factors for the social development. Based on multi-source remote-sensing data from different years, changes in the lake area and oasis in Xinjiang (1972-2008) are analyzed, and the reasons and impact factors for the changes in typical years are pointed out. We find that precipitation is one of the most important factors, and human activity such as agriculture irrigation in the catchments shown as oasis change has great influence on lake area. Furthermore, the detailed influences on the water quality, desertification and waterside vegetation are discussed, and a conclusion is reached that the lake area is the most important factor to ensure the nice environment of the watershed and the key index to measure the environment balance. In the end, some suggestions related to the lake protection are proposed.