An electrical plug connector includes a metallic shell, an insulated housing, and a grounding sheet. The insulated housing is received in a receiving cavity of the metallic shell and includes a mating room and side assembling cavities. The side assembling cavities are defined at two sides of the insulated housing and communicate with the mating room. The grounding sheet is at the insulated housing and in contact with the metallic shell. The grounding sheet includes a main body in the insulated housing, side arms extended toward the side assembling cavities from two sides of the main body, hook portions extended toward the mating room from the fronts of the side arms, and mounting legs extended from the rears of the side arms and protruded from the side assembling cavities.