A GPS (Global Positioning System) antenna module includes a substrate, a first insulating layer, and a second insulating layer. The substrate is set on a bottom surface of a patch antenna. The first insulating layer is coated on the substrate and a layout circuit is formed thereon. A plurality of electronic elements are integrated on the substrate according to the layout circuit. Furthermore, the second insulating layer is coated on the first insulating layer to completely shield the electronic elements integrated on the substrate. Hence, the distance between the electronic elements and the antenna of the present invention can be shortened, space on the PCB and in the shielding case is saved. Moreover, an optimal high frequency character can be achieved, the volume of the antenna module is effectively reduced, the process is simplified, and production costs are reduced.