The image forming apparatus has a communicating portion from the first chamber
24 to the second chamber 25, and a communicating portion from the
first chamber 24 to the third chamber 26, which are separated from
each other. With this structure, an active flow of fresh toner into the third chamber
26, where a developer having a low toner ratio and low toner concentration
is stirred together with recycle toner during an image forming operation is suppressed.