In this paper, we present the statistical characteristics of Non-Gaussian sea surfaces, and find suitable statistical indicators to distinguish the rough surfaces generated by different parameters. Firstly, according to the sea surface height and wave spectrum, the rough sea surface is modeled. Then the non-Gaussian rough sea surface is constructed by using the SAR geometry. Finally, the roughness index is generated according to the SAR imaging results. The method can allow more degrees of freedom when generating a non-Gaussian rough sea surface, rather than just specifying the difference of skewness and kurtosis. Results analysis verifies the effectiveness of the proposed method.