A SBR-VRT hybrid method combining the bouncing ray method (SBR) and the vector radiative transfer equation (VRT) is proposed in this paper. The basic idea of the hybrid method is illustrated. The composite scattering of a tank located above a rough ground surface covered by vegetation is calculated. The influence of different incident wave frequencies on the composite scattering results is discussed. By comparing the simulating results in the S-band and L-band, it can be found that: the values of ground scattering and composite scattering are in general agreement when the incident angles less than 10°. With the increasing of the incident angle, the total scattered coefficient decreases firstly and then increase, which reaching an interval peak at 25°, and finally decrease.