The present invention provides a touchpad with a double-layer printed circuit board structure. The touchpad comprises an upper layer, a bottom layer, a first conductor; and a second conductor; wherein the upper layer is configured to act as a touch-sensitive zone, and comprises a plurality of first conductive units, a first conductive wire and a plurality of second conductive units; the bottom layer comprises a wire connecting zone and a component zone, wherein the wire connecting zone further includes a second conductive wire and a connecting line configured to be electrically coupled to the component zone; and the first conductor and the second conductor are configured to connect the upper layer to the bottom layer; wherein the first and the second conductive units are each serially-connected to form a first touch-sensitive line and a second touch-sensitive line, respectively.