To prevent developer sticking to the carrying face as of a transfer belt from being transferred to a sheet unnecessarily.

The image forming device 10 has a photoreceptor 12, the transfer belt 36, a transfer roller 40 for transferring powder developer on the photoreceptor to the transfer belt 36, and a cleaner 22 for recovering the residual developer from the photoreceptor 12. A switching device 48 switches the transfer roller 40 back and forth between a first condition in which the developer is transferred from the photoreceptor 12 to the transfer belt 36 and a second condition in which the developer is reversely transferred from the transfer belt 36 to the photoreceptor 12. Other switching device 58 switches a recovering roller 50 back and forth between a condition in which the developer is recovered from the transfer belt 36 and a condition in which the recovered developer is released to the transfer belt 36 again. The developer released to the transfer belt 36 is reversely transferred onto the photoreceptor 12 and thereafter recovered to the cleaner 23. This prevents transfer of the unwanted developer to the sheet from the transfer belt 36.