A heat dissipation module is suitable for being assembled on a circuit board to dissipate the heat source on the circuit board. The heat dissipation module includes a holding unit, a fan and a cover unit. The holding unit is formed by a holder base and multiple first support posts extending from the holder base downwards, each of the first support posts has an elastic snap sleeve to be snapped in a snap hole and the elastic snap sleeve has an accommodation space. The fan is assembled on the holder base and the cover unit covers the fan and is assembled on the holding unit, and an end of each second support post of the fan has a snap tenon plugged in the accommodation space.