The present invention is to provide a water-and-dust proof structure for a notebook computer heat sink having a chip set and a heat sink module, characterized by comprising (between the chip set and the heat sink module): a separation plate comprising a receptacle having a prescribed hole therein, the separation plate cooperating with a casing of the notebook computer to form a space inside the notebook computer so that the heat sink module and the chip set on the main board of the notebook computer are separatedly located in different spaces inside the notebook computer and closely contact each other through the receptacle of the separation plate; a resilient frame formed to cooperate with the receptacle of the separation plate and having a prescribed hole therein; a resilient piece formed to cooperated with the prescribed hole and having multiple resilient curve portions; and arranging the resilient frame into the receptacle of the separation plate, the heat sink module cooperating with the resilient piece to connect with the chip set through the prescribed hole and fixed on the separation plate.