An image forming apparatus capable of suppressing drop in the write positional accuracy of the optical write while improving the maintenancability of the photosensitive bodies and the peripheral devices thereof, having a printer comprising four processing units each holding, in the inner part thereof, a photosensitive body for supporting a latent image on an endless moving surface, an optical write unit that is movable between an operate position where a write operation is performed for writing latent images on the surface of each of these photosensitive bodies and a retreat position where this write operation is not performed, and a support body for supporting each of the photosensitive bodies of the processing units and the optical write unit, the support body being configured as an integrally molded part by being united at the location for supporting each of the photosensitive bodies of the processing units and the location for supporting the optical write unit from (front-side panel and rear-side panel).