An exemplary electronic device includes a printed circuit board, electronic components mounted on a top surface of the printed circuit board, and a heat dissipation device. The heat dissipation device contacts the electronic components to absorb heat generated from the electronic components and dissipate the heat by natural convection and thermal radiation. The heat dissipation device includes a base plate contacting the electronic components to absorb heat generated therefrom and thermal hairs mounted on a top surface of the base plate. The thermal hairs wave with heated airflow at an inner of the electronic device to dissipate heat transferred from the base plate.