According to the structure strength optimization theory, each concave die layer's size and inter layer interference were obtained by using the Lame formula. The end angle and stage height were introduced into the finite element optimization model. Setting the maximum equivalent stress reached the material's allowed stress as the optimization object, the optimization parameters of the staged oblique end combined concave die were obtained. Compared with the flat end combined die, the total diameter and the inside diameter of staged oblique end combined concave die are decreased obviously.