A wire-to-board connector for coupling electrically a circuit board to a transmission wire unit, includes a plug receptacle, a plurality of signal contacts and a mating header. The plug receptacle is mounted on the circuit board. The mating header includes an insert body that is disposed at one end of the transmission wire unit and that has a plurality of resilient metal elements. When the insert body is plugged into the plug receptacle, the resilient metal elements respectively contact with the signal contacts of the plug receptacle, thereby establishing electrical communication with the circuit board and the transmission wire unit.