A plug connector includes an insulating housing, a plurality of first terminals which are adapted to connect with a mating receptacle connector and include a first ground terminal, a first power terminal for connecting with an external power supply and at least two first signal terminals, a plurality of second terminals which include second power terminals adapted to transmit different voltage values, second ground terminals and a backup terminal, and a support body mounted to a rear side of the insulating housing. The first and second terminals are inserted forward in the insulating housing and each has a soldering arm penetrating rearward through the support body to be exposed outside and supported by the support body. A shielding shell encloses the insulating housing and the support body with the first and second terminals.