An image forming apparatus comprising a first body and a second body which are openable or separable from each other. The apparatus contains a plurality of developing devices, each of which is movable between its developing position for developing a latent image on an image bearing member of the image forming apparatus and a retracted position where the developing device is retracted from the developing position. At least the developing device that is located at its developing position when the apparatus is closed, is moved away from the image bearing member in response to an operation for opening the second body relative to the first body.