As an important part of the terrestrial hydrosphere,lake is an essential information carrier for revealing global climate change and regional response. Spatiotemporal variation characteristics of lakes in Qinghai Province from 1990 to 2015 were obtained by using remote sensing technology,and the responses of lakes to climate change were explored based on the spatiotemporal variation characteristics of temperature and rainfall in Qinghai Province in recent 25 years. Results show that the lake area has increased from 12 757 km~2 to 15 167 km~2 and that the number of lakes has increased from 241 to 286 in Qinghai Province over the past 25 years. The spatiotemporal variations of lakes are very different in different regions,including Eastern region(Ⅰ),northwest region(Ⅱ) and southwest region (Ⅲ). Precipitation enhancement promoted the increase of lake area and quantity in the area Ⅰ where lake area increased from 7 173 km~2 to 8 474 km~2 and where number of lakes increased by 19. In the area Ⅱ,lake area increased from 1 369 km~2 to 1 542 km~2,and number of lakes increased by 7. The area Ⅱ is located in the Qaidam Basin,which is one of the arid areas in china with dry and rainless climate and small lake area. The main factor for lake expansion is the increase of rainfall and main factor for lake shrinking is lake evaporation. Lake area of the area Ⅲ increased from 4 215 km~2 to 5 152 km~2,and number of lakes increased by 19. The lake expansion in the area Ⅲ is due to the increase of rainfall and decrease of evaporation. The basic data for scientific utilization of lake and rational allocation of water resources in Qinghai Province were provided in this study.