After completion of a preceding painting in a preceding painting area, by an action of a preceding painting robot, a painting object (object to be painted) is caused to be held together with a holder by a transfer section near two painting areas. In succession, with maintaining connection between the painting object and the holder, connection between an arm leading end portion of the preceding painting robot and the holder is released. Thereafter, by an action of a subsequent painting robot, an arm leading end portion of the subsequent painting robot with keeping its connection to the painting object is connected to the holder held to the transfer section. With this, in the course of transfer of the painting object between the painting robots for displacing the painting object relative to a spraying means, a relative positional relation between the arm leading portions of the painting robots and the painting object can be maintained same.