To prevent the output speed from getting lower in the case of performing cleaning by a cleaning device on an image carrier side by transferring toner or the like, adhering to a transfer belt to the image carrier side.

This toner image transfer device 6 is constituted by stretching and laying the transfer belt 63 between a 1st transfer roller 61 brought into press-contact with a photoreceptor 2 and a 2nd transfer roller 62 separated from the photoreceptor 2 and positioned on a downstream side in a sheet carrying direction. In such a case, the peripheral length of the belt 63 is set to be equal to or shorter than space (sheet distance) between carried sheets. In the sheet distance obtained until the leading edge of the next sheet reaches after the sheet passes through a transfer position, cleaning voltage is supplied, so that the toner or the like, adhering to the belt 63 is transferred to the photoreceptor 2, and removed by the cleaning device 7 on the photoreceptor 2 side. Thus, all the periphery of the belt 63 is cleaned by utilizing the sheet distance and excellent cleaning ability is secured without making the output speed lower.