To provide an electrostatic spray coating method by which electrostatic spray coating using a water-soluble coating material can be safely performed under an internal application method and with high efficiency and countermeasures for insulating the subject device is simplified, and further, spray coating failures such as overspray and spray insufficiency are prevented from occurring, in the electrostatic spray coating for an automotive body by intermittently actuating a pray gun G as well as the spray coating device.

This electrostatic spray coating method is to make the layout of a spray coating line by connecting a coating material tank T, a nitrogen gas supply part 2 and a hot water supply part 3 to a spray unit 8 with the spray gun G installed at a robot arm R though a signal selection/conversion unit 5 and a sending pump 6 and pool a one shot amount of the coating material P of a specific color in a coating material pool part 22. Further, the method is to form an insulating zone 40 in the middles of a sending hose H by sending nitrogen gas N following the one shot coating material and apply high voltage to the latter half part 42 only of a line from the insulating zone 40 to the spray gun G to perform the intermittent electrostatic spray coating, and further, clean a coating material flow channel with hot water W. The spray coating device 1 is also provided.