The invention belongs to the technical field of mechanical processing, and particularly relates to a tapping device for a stop ring of a clutch machine cover. A rotary motor is arranged on a base; a rotary shaft is arranged on the top of the rotary motor; the outer surface of the rotary shaft is sleeved by the stop ring; a first processing motor and a second processing motor are further arranged on the base; a first processing shaft is further arranged on the top of the first processing motor; a second processing shaft is arranged on the top of the second processing motor; a drill spindle and a screw tap are arranged above the stop ring; the drill spindle passes through a first circular hole; the screw tap passes through a second circular hole; a drill spindle limiting block is arranged on the top of the drill spindle; a screw tap limiting block is arranged on the top of the screw tap; the drill spindle limiting block and the screw tap limiting block are positioned on the upper surface of a supporting plate; the drill spindle and the first processing shaft are sleeved by a first synchronous belt; and the screw tap and the second processing shaft are sleeved by a second synchronous belt.