The traditional method of calculating electromagnetic scatterings from the rough sea surface, which does not need a geometrical sample of sea surface, considers mainly the total scattering echoes by average assembling of different incident parameters. With the development of synthetic aperture radar and radar imaging, it is important to fully describe the sea surface at every point, and to obtain the result of electromagnetic scatterings from the facets of the rough sea surface. Meanwhile, with increasing wind speed above the sea surface, the influence of the sea foam layer on the scatterings will increase. In this paper, the facet-model is considered, and taking into account the impact of the foam layer on the scatterings at a large angle incidence, the backscattering coefficient is calculated for different wind speeds; and the result of numerical simulation is compared with the experimental data to verify the accuracy of our method.