An image forming apparatus includes image forming portions each including an image bearing member, a charging portion, an exposure portion, a developing portion including a developing member, and a cleaning member; a contact-and-separation portion; a voltage source; and a control means. An operation is executed in a contact state of the developing member with the image bearing member at the image forming portion where the image is formed, in a separated state of the developing member from the image bearing member at the image forming portion where the image is not formed and in a state in which the image bearing members of the image forming portions where the image is formed and is not formed are driven. When the operation is continuously executed, the control means executes a contacting operation at the image forming portion where the image is not formed.