Abstract: In view of the fact that the Ordinary Kriging algorithm will be influenced by outliers while processing multibeam bathymetry data. The calculating formula of sample variogram is deduced by robust estimation, and the influence of outliers in fitting variogram function is eliminated. The superiority of the algorithm in exactitude estimating and detecting outliers is proved by real data experiments. The regular square grids of multibeam data are also constructed by the algorithm. The grids values are compared with which is calculated by manual processing, and they are consistent; hence the feasibility is proved that the seabed terrain grids can be constructed by our algorithm in high precision while outliers is detected automatically.