A composite antenna substrate and semiconductor package module includes: a fan-out semiconductor package including a semiconductor chip, an encapsulant encapsulating at least portions of the semiconductor chip, and a connection member including a redistribution layer electrically connected to connection pads; and an antenna substrate including an antenna member including antenna patterns, ground patterns, and feed lines, and a wiring member disposed below the antenna member and including wiring layers including feeding patterns electrically connected to the feed lines.