Abstract: The present invention relates to a 2-layer printed circuit board (PCB) for enabling impedance matching of a high frequency signal line, and a method of manufacturing the 2-layer PCB. In the present invention, an insulation layer with a predetermined thickness is formed as an insulation substance on a top surface of a signal layer formed on a general 2-layer PCB so as to protect a high frequency signal line formed on the signal layer. An auxiliary layer selectively including carbon, a PCB, a tape in the form of copper foil or the like is formed on a top surface of the insulation layer. At this time, the thickness of the insulation layer is determined to be different depending on a material of the auxiliary layer. Further, the auxiliary layer and a ground layer provided to the 2-layer PCB are electrically connected to each other. Then, the auxiliary layer serves as a ground plane.