A heat sink includes a heat sink body having a plurality of stacked fins and a mounting base including a heat dissipation plate. A first surface of the heat dissipation plate is connected to a lower portion of the heat sink body. A protrusion protruding away from the heat sink body is disposed on a portion of a second surface of the heat dissipation plate opposite to the first surface. The protrusion is formed by stamping or bending the heat dissipation plate away from the heat sink body from the first surface of the heat dissipation plate.