Embodiments of the present invention provide a heat dissipation device of a notebook computer. The notebook computer is provided with a keyboard. The heat dissipation device includes a heat dissipation component and a heat guiding box, the heat dissipation component is communicated with the heat guiding box, the keyboard is also communicated with the heat guiding box, and the heat guiding box is used to transmit heat in the heat dissipation component to the keyboard.