The invention relates to the technical field of machining, in particular to a machining locking device for a locomotive wheel. The machining locking device for the locomotive wheel comprises a shaft sleeve, a ratchet wheel, a pawl, shifter levers and an adjusting bolt. The ratchet wheel is arranged outside the shaft sleeve in a sleeving mode and fixedly connected with the shaft sleeve. The two shifter levers are arranged outside the shaft sleeve in a sleeving mode and are located on the two sides of the ratchet wheel respectively, the shifter levers are fixedly connected through bolts, an adjusting block is arranged between the shifter levers and movably connected with the shifter levers, and the adjusting bolt is located on the adjusting block. The pawl matched with the ratchet wheel is arranged between the shifter levers. By means of the cooperation of the shifter levers and the ratchet wheel, the shifter levers can only rotate in the direction opposite to the moving direction of a clamping jaw; the shaft sleeve is fixedly installed on an axle, one ends of the shifter levers are in contact with a clamping jaw arm, the clamping jaw can drive the axle to move together through the shifter levers, relative sliding between the clamping jaw and the wheel is avoided, machining efficiency is improved, and machining precision is improved.