An electrical connector includes an insulative housing having a mating cavity and a plurality of power contact pairs. Each power contact pair defines an upper contact set and a lower contact set, each one of the upper contact set and the lower contact set comprises a first contact unit and a second contact unit, each one of the first contact unit and the second contact unit has a retaining portion and at least one contacting portion extending from the retaining portion into the mating cavity. The retaining portions of the upper contact set are arranged in a height direction of the insulative housing with the contacting portions thereof arranged in a transverse direction of the insulative housing, the retaining portions of the lower contact set are arranged in the height direction with the contacting portions thereof arranged in the transverse direction.