The invention discloses a nanocomposite road marking coating material. The nanocomposite road marking coating material comprises the following ingredients in parts by weight: 20-30 parts of glass powder, 6-10 parts of aluminum oxide powder, 50-80 parts of filler, 30-40 parts of epoxy resin, 15-20 parts of aqueous epoxy modified acrylate, 15-20 parts of glass micro-beads, 10-20 parts of chitin, 15-20 parts of chitosan, 20-40 parts of nano titanium white, 15-20 parts of nano zinc oxide, 10-15 parts of nano-silica, 2-4 parts of 25wt% ammonia water, 30-40 parts of acrylic emulsion and 15-20 parts of nano rare-earth self-luminous material. The invention further discloses a preparation method of the nano coating material. The nanocomposite road marking coating material disclosed by the invention is high in drying speed and long in service life, is wear-resistant and anti-fouling and has a bacterium resisting effect, and nano-materials or nano-structured ingredients are introduced into an organic coating material, so that organic and inorganic matched compositing or hybridization is realized. The advantages of organic polymers and inorganic-structured ingredients are integrated, so that the properties of the coating material are obviously improved.