An image forming apparatus includes an image forming unit and a plate. The image forming unit is configured to be detachable from the image forming apparatus. The image forming unit includes a convex portion. The plate includes a hole configured to receive the convex portion. The image forming unit further includes a lever which is provided at a front side of a unit case of the image forming unit and is configured to move between a working position and a storing position. When the lever is moved from the storing position to the working position, the convex portion is removed from the hole.