A power adapter cable is adapted to be connected between a charger having mating electrode passages with mating electrode pins therein and a power plug having mating electrode plugs with mating inserting holes. The power adapter cable includes an adapter plug having a base, an adapter socket having an insulating body and a wire connected therebetween. A front surface of the base is protruded forward to form electrode plugs with inserting holes passing therethrough. The electrode plugs of the adapter plug are inserted into the mating electrode passages of the charger with the mating electrode pins being inserted into the inserting holes. A rear surface of the insulating body is recessed inward to form electrode passages with electronic pins therein. The mating electrode plugs of the power plug are inserted into the electrode passages of the adapter socket with the electrode pins being inserted into the mating inserting holes.