The invention discloses an automobile air conditioner top evaporator which comprises an evaporator shell, a motor, an air blow gun and an electric push rod. An evaporator core is arranged on one side of the outer surface of the evaporator shell, and the other side of the outer surface of the evaporator shell is connected with an air inlet pipe. The motor is fixedly installed on one side of the interior of the evaporator shell through bolts, and a first belt wheel is welded to the output end of the motor. A lead screw is arranged in the evaporator shell through a bearing, and the lead screw is connected with a first sliding block in a sliding mode. A dust removal box is welded at one end of the first sliding block, and a second belt wheel is welded to the lead screw on one side of the first sliding block and connected with the first belt wheel through a transmission belt. A rotating shaft is mounted in the dust removal box through a bearing, the air blow gun is fixedly mounted in the middle of the rotating shaft, a fixing rod is welded to one end of the air blow gun, and the electric push rod is welded in the dust removal box. Dust removal and defrosting for the automobile air conditioner top evaporator can be achieved.