A switching device of electrical plug connector includes a plug body, a circuit board and a switching member. The plug body includes a connecting shell and an inserting space. The circuit board is disposed at the plug body and connected to a plurality of conductive plates. The switching member is connected to the circuit board and includes a transmission bar, a contact plate and an elastic member. The transmission bar passes through the circuit board; one end of the transmission bar is disposed in the inserting space. The contact plate is disposed adjacent to the conductive plates and connected to another end of the transmission bar. The elastic member sleeves on the transmission bar. When an electrical receptacle connector inserts into the connecting shell, one end of the transmission bar is abutted to drive another end of the transmission bar moving, thereby connecting the contact plate with the conductive plates.