Abstract: Disclosed is a method for evaluating thicknesses of cobalt-rich crusts on seamounts, which comprises following steps: dividing a study area of cobalt-rich crusts into geological grid units, assigning crust thickness values to geological grid units; obtaining the crust thicknesses of the geological sampling stations in a preset influence range in the adjacent areas based on geological sampling station information; estimating the crust thicknesses in a certain distance range of the stations by a “distance-slope” spatial interpolation method, and through a spatial similarity of a crusts spatial distribution caused by a relationship between the distance and the slope, assigning values to grid units outside adjacent areas and within an influence range of the spatial similarity relationship; assigning values to the geological grid units that failed to obtain crust thickness value through an expected assignment method, and obtaining the crust thicknesses of the study areas.