An electrical connector includes a terminal module unit with contacts and grounding plates thereof. The terminal module includes an insulative base and an insulative mating tongue forwardly extending therefrom. The mating tongue forms opposite mating surfaces. The contacts includes the contacting sections on the mating surfaces and the connecting legs. The mating tongue includes a root section adjacent to the base. The grounding plates unit covers the root section in an embedded manner. The grounding plate includes a planar body exposed upon the mating surface, and a pair of fixing side arms extending from two opposite ends of the planar body and equipped with corresponding latching hooks to secure to the semi-finished root section before the final insert-molding process is applied.