This dissertation employs the method of direct current (DC) magnetron sputtering on the reverse side of the high power LED aluminum substrate to deposit the AlN thin film. And then, we paste the high power LED beads to the front of the substrate, testing and studying the heat dissipation influences of the AlN thin film on the high-power LED beads. In order to compare easily, some parts of the reverse of aluminum substrate should be overlaid thermally conductive silicone. The result indicates that depositing the AIN thin film or the overlay thermally conductive silicone on the back side of the aluminum substrate can improve the heat dissipation capability of high power LED, the AIN thin film especially.