A fixing device for an image forming apparatus of the present invention includes a pressing/transferring member for pressing, when a toner image transferred from a photoconductive drum to a first image transfer body by primary image transfer is to be transferred to a second image transfer body by secondary image transfer, the second image transfer body against the first image transfer body. A heat-fixing member heats the second image transfer body after the secondary image transfer to thereby fix the transfer image on the second image transfer body. A press-fixing member presses the second image transfer body against the heat-pressing member. A belt conveyor conveys the second image transfer body from a nip for secondary image transfer between the first image transfer body and the pressing/transferring member to a nip for fixation between said heat-fixing member and the press-fixing member.