A heat dissipation device includes a heat conducting base, a heat sink on the base and two heat pipes thermally contacting with the heat sink and the base. The heat sink is made of metal extrusion and includes a heat conducting cylinder at a periphery of the heat sink and a plurality of fins extending from and surrounded by the cylinder. The cylinder includes four interconnected sides. The fins of the same side are parallel to each other. The two heat pipes thermally surround the cylinder of the heat sink and wholly contact the heat sink.