An adjustable heat sink assembly includes a thermo-conductive bottom panel having a flat contact face protruded from the bottom wall thereof, elevation-adjustment fasteners mounted in the thermo-conductive bottom panels and fastened to a circuit board and vertically adjusted to keep the flat contact face in positive contact with a heat source at the circuit board, a thermo-conductive top panel, pitch-adjustment fasteners joining the thermo-conductive bottom panel and the thermo-conductive top panel and adjustable to control the distance between the thermo-conductive bottom panel and the thermo-conductive top panel and to keep the thermo-conductive top panel in positive contact with the housing, face panel or radiation fin of the electronic apparatus using the circuit board, and heat pipes connected between the thermo-conductive bottom panel and the thermo-conductive top panel.