A power connector includes an insulative housing, a number of contacts retained in the insulative housing and a spacer fixed to the insulative housing. The insulative housing includes a mating surface, an end surface opposite to the mating surface and a plurality of first passageways extending through the mating and the end surfaces. A depression and a cavity are recessed into the insulative housing from the mating surface and the end surface, respectively. Each first contact includes a main portion received in the corresponding first passageway and a tail portion located at the cavity in condition that at least one side wall of the tail portion is exposed to the outside for excellent heat dissipation.