Provided are an enamel coating method and apparatus. The enamel coating method includes (a) preprocessing a surface of the metal tube by feeding the metal tube into a preprocessing chamber by an in-feed conveyor; (b) coating the surface of the metal tube with an enamel glaze supplied from an enamel glaze supply nozzle provided inside a coating chamber by feeding the preprocessed metal tube into the coating chamber; and (c) firing the coated metal tube by feeding the coated metal tube into a firing chamber, wherein the (b) coating includes spraying air toward the metal tube by an air spray nozzle provided inside the coating chamber.