Abstract: On the ground of hypothesis that the change of marine terrain is continue and slow,a new method of detecting outliers of multi-beam data by Bayes estimate theory is presented.In order to verify the validities and rationalities of this method,a contrast between this method and the approach of select-weight iterative filter is done.The result shows that the approach can solve the problem of judge-standard reliability and could detect the outliers of Multi-Beam data valid and rational.