A transfer device includes a transfer device controller for controlling the whole transfer device, a storage for storing various kinds of data etc. necessary for control, an intermediate transfer unit including a primary transfer power supply and its driver, a secondary transfer unit including a secondary transfer power supply and its driver, and a PTC unit. In the transfer device, a controller communicates with a main controller that controls the whole image forming apparatus, and acquires, for example, information on the total print count or the like. When PTC radiation is determined to be needed based on the above information, the controller controls to drive the PTC unit.