Abstract:In order to improve the interpolation accuracy of meteorological elements, the meteorological data were firstly processed, and then the changed data were interpolated. The 40 a meteorological data during 1961-2000 and the observation data of 2005 from 743 conventional stations in China, the interpolation methods including IDW, Kriging and Spline, and the data pretreatment method was processed based on anomaly processed. Results show that IDW is better than Kriging and Spline for average temperature anomaly; the improvement of temperature is better than that of precipitation and relative humidity; precipitation anomaly deviation presents the increasing trend from east to west. Thus, the pretreatment methods of meteorological data can improve interpolation accuracy.