Using the monthly mean temperature and monthly precipitation of Dongsheng and Etuoke stations in Erdos from 1957 to 2010,the paper analyzed the evolution rule of temperature and precipitation ,and estimated the land evaporation by using Gaoqiao equation, and its variation rule. The results showed that the air temperature has been increased sharply since 1990's, and the range of increase in Dongsheng at east of Erdos is more than that of Etuoke at west of Erdos. The significant warming also appeared in 1990's in four seasons.The increase of temperature is relatively slow in summer,And that in other three seasons is more significient. Precipitation of the two stations presents a decreasing trend, and the range of decrease in Dongsheng is more than that in Etuoke. The precipitation variation trend is not obvious in Spring and Winter, but it appears a decreasing trend in Summer and Autumn.The land evaporation of the two stations appears the trend of increase, and the land evaporation has been obviously rising since 1990's. The average annual land evaporation in Dongsheng is higher than that in Etuoke. Land evaporation in Spring, Summer and Winter presents the increasing trend, and that in Autumn is the decreasing trend. Precipitation affects significantly the difference between evapotranspiration and precipitation, and the available precipitation possesses the trend of decrease.The decrease trend is obvious in Dongsheng at east of Erdos.