How to transfer the scattered observed station data into the regular grid data is vital to the research of climatic change and simulation, which needs spatial interpolation method to achieve. The inter-comparison is made among Kriging, Inverse distance weighting, Delaunay triangulation linear interpolation, Biharmonic spline and Cressman objective analysis spatial interpolation based on observed scattered station precipitation data over China. The advantages, disadvantages and application areas of every spa...