The image forming apparatus has an image bearing member, a detecting member, a toner image forming apparatus, a transfer member and a collecting member for collecting toner of a toner image for detection attached to the transfer member rotating while contacting with the transfer member, and removing member for removing the toner collected into said collecting member from the collecting member in a removing area. In the image forming apparatus, a portion of the collecting member contacts the transfer member passes through the removing area by a time when said collecting member next contacts with the transfer member, and by a time when a portion of the collecting member which contacts a portion of the transfer member contacts the toner image for detection next contacts the portion of the transfer member contacts with the toner image for detection, said collecting member passes through the removing area at least two times.