A hermaphroditic electrical connector assembly comprises a first connector (10a) and an identical second connector (10) to mate with each other, each connector comprising: an insulating housing (20) having a base portion (21), a pair of fixing arms (24) molded two side of the base portion and locating two ends of the diagonal of the base portion separately. and several terminal slots (22) on the base portion; and a number of terminals (5) retained in the terminal slots of the insulating housing; the fixing arms of the first connector engaging with same side fixing arms of the second connector.