The invention discloses a method for producing a transmission part, which comprises the steps of: 1) adopting a punch press for blanking; 2) performing flat head chamfering on a blanked material; 3) producing the blanked material into a blank which satisfies a pressing machine mold in step 5); 4) performing annealing treatment on the blank; 5) performing cold extrusion thickening on the blank; 6)punching a central hole on the thickened blank, chamfering after the reaming, and then turning an external circle; 7) performing cold extrusion curve molding on the blank; 8) performing cold extrusion spline treatment on a workpiece; 9) then performing plane turning and chamfering on the workpiece; 10) then removing an overlong part of a small diameter end of the workpiece through the turning, rough turning a plane, and then chamfering; 11) turning an external circle of a large diameter end of the workpiece into a needed shape, slotting the position, which is near the end surface, of an external circle surface of the small diameter end, and chamfering a central hole of the small diameter end at the same time; and 12) performing flat head chamfering and inner hole reaming on the treated workpiece to obtain a finished product. Compared with the prior art, the method saves the time of working procedures, saves raw materials, and has higher rate of finished products and lower cost.