The invention discloses a part clamping mechanism and a using method thereof. The clamping mechanism comprises a workbench, a cylinder and a flap seat, wherein the cylinder and the flap seat are arranged on the workbench; a connecting rod shaft is arranged in an inner hole of the flap seat and connected with the output shaft of the cylinder; the cylinder drives the connecting rod shaft to move inthe flap seat; the other end of the connecting rod shaft is connected with a clamping plate through a curved connecting rod; the curved connecting rod is fixed on the flap seat through a turnover shaft pin and drives the clamping plate to move vertically or rotate; the curved connecting rod is provided with a curved groove with a certain included angle, and the turnover shaft pin is positioned inthe curved groove; and the curved connecting rod moves in accordance with the curve of the curved groove in different direction by using the turnover shaft pin as a fixed point. The part clamping mechanism keeps the turnover form of a pressure head, ensures that a flap vertically clamps a part, prevents the pressure head from blocking the picking and placing of the part during moving, and meanwhile, ensures that the surface of the part is not scratched during clamping.