In order to solve the multi-wedge belt pulley (MWBP) with transverse outer ribs was difficult to forming ribs and simultaneous forming three ribs, the MWBP with transverse outer ribs was used to study the formation of multi-steps spinning forming process by the SIMUFACT software. The finite element model of spinning forming was established based on the analysis of spinning deformation. The stress field distribution, the deformation of the sheet metal and the metal flowing of the sheet during the 1st to 4th step spinning forming process were analyzed. In this study, it generalized integral quality of parts under different spinning equipment technics parameter, and prove the roller feed speed and the friction to have important impact in filling quality of ribs the integral quality of parts. Three factors and three levels orthogonal experiment were numerically simulated with the independent variables of roller feed speed, friction factor and rotation rate, the data of the maximum forming load and thickening rate of transverse ribs and those data were obtained by the orthogonal experiment. The grey system theory was used in the parameters optimization though the spinning thickening forming of MWBP with transverse outer ribs. The smaller roller feed speed and the friction can ensure filling quality of ribs the integral quality of parts. Those experiments were conducted on the CDC-S100E/R4 spinning machine. The results showed that the original plate thickness was thickened from 3.0 mm to 3.4 mm and the rib region was thickened to 6.9 mm which verified the feasibility of the grey system theory based optimization scheme.