An applying method of a nail polish on a nail surface via an airbrush applicator, including the steps of: filling a predetermined amount of nail polish in a polish container of the airbrush applicator; actuating an air compressor of the airbrush applicator, which is powered by a rechargeable battery thereof, for generating pressurized air; controlling a flow of the pressurized air to mix with the nail polish so as to form an aerosol on the nail surface; and drying the nail polish on the nail surface to form a nail coating thereon.