A fan-out semiconductor package includes a first connection member having a through-hole, a semiconductor chip with connection pads on its active surface disposed in the through-hole and a first encapsulant encapsulating at least portions of the first connection member and the semiconductor chip. A second connection member is disposed below the first connection member and the semiconductor chip. A first heat dissipation member is formed in the first connection member. A component package is disposed on the fan-out semiconductor package and includes a wiring substrate connected to the first connection member through connection terminals, electronic components disposed on the wiring substrate, a second encapsulant encapsulating at least portions of the electronic components, and a second heat dissipation member formed in the wiring substrate. At least one of the electronic components is connected to the first heat dissipation member through the second heat dissipation member.