Abstarct: Precipitation is considered as the main input in the planning of sustainable water resources development. Efficient measuring network is a network of rainguages which, in addition to the proper and accurate measurement, has a desirable density and spatial distribution, in such a way that it is possible to obtain an appropriate estimation of precipitation in ungauged areas in a basin. In this study, a method was used baxsed on Kriging concept and a normal probability distribution function for evaluating the network of rainguages in Mashhad basin with a total area of 9900 square kilometers. This approach is baxsed on a percentage of region's area with Acceptance Probability (AP) method. First, by analyzing the spatial variations of annual rainfall over the basin using a dimensionless variogram, the spatial structure of the precipitation was extracted and then the proposed algorithm was applied. Of the 34 stations, 5 stations were omitted due to lack of information or insufficient information over the historical period. From remaining 29 stations, 19 stations were detected as baxse stations where the remaining 10 stations were assessed to have a very little effect on rainfall estimation in the basin. Also it was found that by installing 6 new stations in some ungauged areas of the basin, the accuracy of rainfall estimation can be increased significantly. With the simplifications carried out in this method and the calculations in the GIS, the results revealed that the proposed method can easily be applied for assessment of raingauge networks.