High-frequency signal transmission device and satellite frequency demultiplier

The utility model provides a high-frequency signal transmission device which comprises a printed circuit board and a signal line, wherein the printed circuit board is provided with a punching zone, a weld zone and an earthing zone; the weld zone is positioned on the periphery of the punching zone; the signal line comprises a central conductor, a dielectric layer and an outer shell layer. The central conductor is provided with a nudity zone and a covering zone, and the nudity zone is only coupled with the weld zone. The dielectric layer covers the covering zone of the central conductor, and the outer shell layer covers the dielectric layer and is coupled with the earthing zone.