This research discloses an ultra wideband system-on-package (SoP). The SoP includes a package body; a first integrated circuit mounted on the package body; a first signal transmission unit connected to the first integrated circuit; a signal via connected to the first signal transmission unit and including a slab line and a trough line; and a second signal transmission unit connected to the signal via. The technology of the present research can transmit ultra broadband signals by minimizing discontinuity of signals appearing during vertical transition that occurs in the course of a signal transmission to/from an external circuit, and a fabrication method thereof.