The utility model discloses a condensing pressure unloading valve for an air conditioner. A top end totally-enclosed plugging structure is adopted, so that the load pressure resisting stability of the unloading valve is enhanced, and a series of problems such as refrigerant leakage, compressor faults and the like, caused by failure of a valve sheet and damage of a choke plug, are solved. The unloading valve is connected between the outlet of a condenser and the air return port of a compressor, and comprises a valve body, the valve sheet, a spring and the choke plug, wherein the valve sheet is arranged inside the valve body; a locking cover cap is arranged at the top end of the valve body; the outer side of an enclosing choke plug can be provided with a locking cover cap to form a totally-enclosed structure, so that the load pressure resistance of the unloading valve is enhanced; and the locking cover cap is welded at the top end of the valve body by argon arc welding.