The invention relates to a quantitative analysis method for submarine topography feature complexity. The quantitative analysis method is characterized in that firstly, the size of a sliding window is divided according to submarine topography data, and the geometric central point of the sliding window is set as an area point; then the change frequency and the change scale of submarine topography elevation in submarine topography change features in an area are studied, and moreover, proceeding from the perspective of mathematic relations, due to the facts that the correlation length or the correlation area of the submarine topography data in the area is made to be associated with the change frequency of the submarine topography data in the area, the root-mean-square height of the submarine topography data in the area is made to be associated with the change scale of the submarine topography data in the area, and two statistics parameters of the root-mean-square height and the correlation length are used for quantitatively expressing change conditions of the complex submarine topography, so that quantitative evaluation is carried out on submarine topography data complexity.