A cable connector assembly (100) comprises an insulative housing having a receiving space (18) extending along a front-to-back direction, and a printed circuit board module (2) received in the receiving space of the insulative housing. The printed circuit board module defines a protruded ridge (24) offset to one side thereof, the protruded ridge extending along a vertical direction, and a groove (185) is defined in the receiving space for accommodating the protruded ridge.