A powder coating system which is provided with a rotating stage which makes a metal cylindrical member rotate while holding its internal circumferential surface, a first booth which covers part of the metal cylindrical member which is held by the rotating stage, and a second booth which holds the first booth. A powder coating introduction nozzle which is provided with a filling port of powder coating and a plurality of powder coating spray ports is provided so that a filling port is positioned at the outside of the second booth and so that the plurality of spray ports can be changed in position in the first booth to face surface parts of the metal cylindrical member. The sprayed powder coating is collected inside the second booth by a flow of air from a blow device and is removed by being sucked up by a powder collector.