The present invention relates to an image forming apparatus so composed that it can be furnished with a plurality of developers (10, 11, 12, 13), can change the developer opposed to the photosensitive body (7) by integrally moving the corresponding developers (10, 11, 12, 13) and can compensate the position of the corresponding developer at the compensating position thereof on the way of an appointed movement and particularly relates to a system by which the positioning accuracy of the developers can be heightened without any waste time, thereby causing a high quality image to be formed. For this reason, the present invention features that the developers (10, 11, 12, 13) can be moved by a motor which can position, the position of the developers can be compensated only in the case that the appointed compensating position is on the most short-cut moving path when changing one of the developers to another developer, and the developers are changed through the most short-cut moving path.