In order to further study the interaction mechanism and the physical nature between detection signal from electromagnetic waves and light waves and the background of irregular surface, which provided scattered model for the detection of radar target and the remote sensing of irregular surface. Two-dimensional band-limited Weierstrass function is used to simulate two-dimensional fractal rough surface. Two-dimensional rough surface scattering field is deduced based on the Kirchhoff approximation. The electromagnetic scattering coefficient and the average intensity coefficient of the rough surface is obtained under the HH polarization. The relationship between scattering characteristics and the harmonic number, the incident wavelength and dimension of fractal surface is discussed through theoretical analysis and numerical calculation. The results show that with the harmonic number and fractal dimension increases, apart from the mirror reflection point, the scattering intensity of the amplitude and its high-frequency component is increased. It provided scattering data for refactoring related statistical parameters of rough surface according to the scattering intensity.