A heat dissipation assembly used for dissipating heat from heat generating electronic components includes a mounting frame, a heat sink and a fan duct. The heat sink is positioned on the mounting frame; the fan duct is attached to the heat sink. The fan duct includes a plurality of first clamping portions, and the mounting frame includes a plurality of second clamping portions corresponding to the first clamping portions. The first clamping portions engage with the second clamping portions to fix the fan duct and the heat sink onto the mounting frame.