In a high frequency module, electronic components are mounted on a mounting surface of a collective substrate including a plurality of unit substrates that include a via conductor electrically conducted to a ground potential in a peripheral portion thereof, and the mounting surface and the electronic components are encapsulated with an encapsulation layer. The collective substrate is cut on the encapsulation layer side, thereby forming a half-cut groove penetrating through the encapsulation layer and extending halfway along the collective substrate in a thickness direction such that the via conductor is exposed only at a bottom surface of the half-cut groove. A conductive shield layer is formed to cover the encapsulation layer and is electrically conducted to the exposed via conductor. The collective substrate is then cut into individual unit substrates each including the conductive shield layer electrically conducted to the ground potential through the via conductor.