【Objective】In this paper,Bosten Lake as the research object, comprehensive analysis of the water area variation of Bosten Lake and its driving factors will be conducted,and also the variation trend of Bosten Lake in 2020 and 2030 will be predicted, thus providing scientific foundation for understanding the causes of water - surface area variations and for offering scientific advise for the rational development of water resources of Bosten Lake.【Method】 Based on four period remote sensing data and 30 years of climate and socio -economic statistical data, by applying 3S technology, principal component analysis and regression analysis to calculate the 1978,1990, 2000, 2015 years four period waters area of Bosten Lake, and find out the driving force of water area change.【Result】(1) Bosten Lake lost about 39.75 km~2 water area from 1978 to 2015 and the whole process of change was not a simple reduction but the process of changing from small to large and small size,characterized by volatility; (2) Principal component analysis result indicated that human factors (population, irrigation area, water amount, irrigation amount) and climatic factors (runoff, temperature,precipitation) were the two major factors affecting the change of Bosten Lake water area. Their contribution rates were 47.793% and 37.818%, respectively in the whole process, which demonstrated that the changes of water area were largely affected by human activity rather than climate change. (3) By establishing a multivariate regression model, we predicted changes of Bosten Lake water area from the year 2020 to 2030. Our regression model suggested that Bosten Lake water area will maintain a continuous reduction trend in the future few year, and water area in 2020 and 2030 years will be 939.226 and 935.34 km~2.【Conclusion】The driving force of lake resource changes is not only climate fluctuations, but also human activities. In the short term, human activities are the mainly affecting factors of the Bosten Lake water resource change. And the human activities interference is growing. These findings provide scientific foundation for understanding the causes of water - surface area variations and for effectively maintaining the stability of the Bosten Lake area through adjustments in land use structure.