Based on the climatic,social and economic data from 1981 to 2010 in Yanchi County of Ningxia Hui Autonomous Region,the impacts of climate change trends and human activities on ecological environment were analyzed using trend analysis and linear regression methods.Results show that from 1981 to 2010,the mean annual temperature in Yanchi County increased at a warming speed of 0.22℃/10 a,the mean annual precipitation declined at a rate of 1.44 mm/ 10 a,and the mean annual evaporation decreased at a rate of 9.85 mm/a,which imply that the climate of the region was in the warming-drying period.The influences of human activities on environment were different in different periods.In the 1980s and 1990s,indiscriminate mining,overgrazing and excessive cutting caused the deterioration of ecological environment.After 2000,a series of protection measures like the"Grain for Green" project and forbidden grazing policies had some positive effects on local ecological environment and the region began to show the ability to defend against natural disasters.In brief,human activities play a major role in the ecoenvironment change.Therefore,rational development and utilization of natural resources can promote the harmonious coexistence of human and ecological environment and guarantee the sustainable development of economy and society in Yanchi County.