The invention discloses a self-cleaning nano coating and a preparation method thereof. The self-cleaning nano coating comprises the following raw materials in parts by mass: 10 to 20 parts of fluorosilicone resin, 3 to 10 parts of a nano material, 0.1 to 1 part of a catalyst and 1 to 3 parts of a coupling agent. The self-cleaning nano coating provided by the invention is endowed with the super-hydrophobic-super-hydrophilic double self-cleaning effect, thereby enhancing the self-cleaning effect, since the fluorosilicone resin and the nano material are added in combination, and the fluorosilicone resin and the nano material synergistically cooperate with each other.