Disclosed is a powder coating method and paint thereof. First, a metal object is applied a voltage. Second, paint is rubbed to carry a static charge, wherein the static charge is opposite to the voltage applied to the metal object. The statically charged paint is then sprayed from a nozzle to the metal object to form a coating covering the metal object surface. The paint composition includes 90 to 99.9 parts by weight of a resin matrix, and 10 to 0.1 parts by weight of a carbon nanocapsule evenly dispersed in the resin matrix.