A connector assembly includes a circuit board, a signal plug and a cable. The circuit board has at least one pair of traces of the same length. The signal plug is disposed at a front side of the circuit board, and has at least one pair of terminals of the same length that are respectively conducted to a paired first signal contacts of the pair of traces. The cable extends from the circuit board in a left-right direction and conducts to the circuit board. An extension direction of the cable is substantially perpendicular to an insertion direction of the signal plug. The cable has at least one pair of differential signal lines that are respectively conducted to a paired second signal contacts of the pair of traces.