In an image forming apparatus, when backside contamination of a recording material occurs, a control portion carries out control so that a plurality of restoring toner bands having a length L1 longer than a circumference L3 of a secondary transfer roller is formed at an interval L2 at positions in which the restoring toner bands can overlap with control images with respect to a longitudinal direction of the secondary transfer roller and then is transferred onto the secondary transfer roller through an intermediary transfer belt. The restoring toner bands transferred onto the secondary transfer roller stagnate on a fur brush rubbing against the secondary transfer roller to remove an electric discharge product deposited on the secondary transfer roller. The toner stagnating on the fur brush is inverted in charge polarity and then is re-transferred onto the intermediary transfer belt through the secondary transfer roller. The toner stagnates on a belt cleaning device to remove the electric discharge product also from the intermediary transfer belt.