Abstract: In this paper, we examine the scattering properties of rough differently correlated surfaces using the IEM model. The effective correlation length of such a surface is pointed out and its effect on the backscattering behavior is discussed. It may be found from the cases considered here that the non‐Gaussian effects are very significant even with the same correlation length and height variance. This can be seen from the surface spectra where the roughness scales are distributed. Among the non‐Gaussian correlated surfaces, the exponential correlated has more small scale roughness at the high frequency components.