An image forming apparatus includes: a primary transfer section which
executes a first transfer by superimposing respective color toner images
formed on a plurality of photoreceptors onto an intermediate transfer
member; a secondary transfer section including a transfer roller, which
concurrently transfers a plurality of toner images superimposed and
formed on the intermediate transfer member onto a sheet conveyed from a
sheet feed tray, which is in contact with the intermediate transfer
member, and a high voltage power source which applies voltage to the
transfer roller; and a controller which judges whether there is residual
toner, which is a toner image formed onto the intermediate transfer
member but not transferred onto the sheet when a sheet sensor detects the
sheet exhaustion, and executes a cleaning mode in which the transfer
roller is cleaned when there is the residual toner.