Through secondary development of estimating average rainfall in artificial precipitation operation regions,the rainfall distribution of different attribute precipitations by various interpolation algorithms and the rainfall distribution in different grid intervals by the same interpolation algorithm were studied using interpolation algorithms of Surfer 8.Results showed that the first selected interpolation algorithm for rainfall amount of convectional precipitation was radial basic function method and for mixed precipitation,the least curvature method was best.The interpolation grid intervals for the rainfall distribution of convectional and mixed precipitation were 0.1° ×0.1°.The estimated value of average regional rainfall by inverse distance square method was unaffected by grid interval,markedly lower than that by arithmetic mean method.For convectional precipitation,when the gridinterval was0.1° × 0.1° or even smaller,the estimatedvalues by other four kinds of interpolation algorithms were lower than that by arithmetic mean method,while for mixed precipitation,the valueswere basically unaffected by grid intervals and equivalent to that by arithmetic mean method.