Abstract: There are many influence factors of designing multi-wedge die.In this paper,the actual spread span of interior wedge and interface angle were studied by experiment and finite element analysis.Meanwhile,a new optimization design method for multi-wedge die was developed.The paper suggests that an effective strain is a standard of judging uniform deformation within multi-wedge rolling.The optimal parameters for the design of railway axles die were obtained.The results have an instructional action for designing multi-wedge die.