A fan-out semiconductor package includes: a core member having a through-hole and having first fiducial marks disposed on an upper surface thereof in the vicinity of the through-hole; a semiconductor chip disposed in the through-hole and having an active surface having connection pads and second fiducial marks disposed thereon and an inactive surface opposing the active surface; an encapsulant encapsulating at least portions of the semiconductor chip; and a connection member disposed on the active surface of the semiconductor chip and including a redistribution layer electrically connected to the connection pads of the semiconductor chip, wherein the first fiducial marks are disposed to be symmetrical to each other with respect to a center of the through-hole on a plane view, and the second fiducial marks are disposed to be symmetrical to each other with respect to a center of the semiconductor chip on the plane view.