A new method on optimizing and designing the rolling shear mechanism is proposed in this paper. In this method, the lengths of critical rods and initial crank angle are viewed as design variables, the upper shear blade closest to the pure rolling shear in the shearing stage is viewed as objective function and the maximum mouth opening, the mechanism configuration, the lowest locations of check points on upper shear blade and shear angle are viewed as constraints. The differences between the optimization method of rolling shear mechanism and exist methods are as follows: the objective function is established based on...