A novel method was used to fabricate AIN coating on graphite substrate. This approach included two steps: firstly, the emulsion composed of BN and anhydrous ethanol was sprayed on the surface of the graphite substrate; secondly, AIN coating was formed through the in-situ reaction of Al with the sprayed BN. The reaction was investigated by thermogravimetric-differential thermal analysis (TG-DTA), and the phase composition in the synthetic process was characterized by X-ray diffraction (XRD). Scanning electronic microscopy (SEM) was used to observe the morphology, and electron probe microanalysis (EPMA) was used to observe the distribution of the elements. The experimental results show that the AIN coating is dense and bonded with graphite tightly.