A electrical plug mechanism and electrical receptacle is described. The present invention has an electrical plug, a plug guard and an electrical receptacle. The electrical plug has an end surface, and a plurality of protruding plates and a plurality of holes are defined on the end surface. A plurality of shafts correspond to and travel through the holes of the end surface. The plug guard has hollow protrusions corresponding to the protruding plates of the electrical plug, grooves corresponding to the hollow protrusions and holes corresponding to the shafts. The electrical receptacle has holders corresponding to the protruding plates.