Abstract: The multiple scattering of the complex targets has great influence on the accurate radar cross section(RCS) prediction of the target. A new method  based on the graphic electromagnetic computing(GRECO) platform utilized the visualization character of the GRECO. The pixel was regarded as basic computation unit in this method. Employing geometric optics and physical optics in the electromagnetic computation theory, the RCS computation of the complex target was achieved after the acquisition of the pixel geometrical information and the search of the pixel pairs which meet the criterion of the multiple scattering. The computation examples of the dihedral corner reflector and the missile which are modeled with AUTOCAD software are given. Excellent agreement with the data from other literature indicates that the method has practical engineering value.