This disclosure provides a package substrate, a flip-chip package circuit and their fabrication method. The package substrate includes: a first wiring layer having a first metal wire and a first dielectric material layer filling the remaining part of the first wiring layer except for the first metal wire; a conductive pillar layer formed on the first wiring layer and including a metal pillar connected to the first metal wire, a molding compound layer with a protrusion part surrounding the metal pillar, and a second dielectric material layer formed on the molding compound layer; a second wiring layer formed on the conductive pillar layer and including a second metal wire connected to the metal pillar; and a protection layer formed on the second wiring layer.