The present invention provides an image forming apparatus main body for forming an image on a recording medium using consumable items removably attached thereto by at least two operation modes. The image forming apparatus main body comprises a communicating unit that communicates with a consumable item which retains switching information to change the operation mode of the image forming apparatus main body and a controller that switches among the operation modes according to the switching information retained in the consumable item when the consumable item is attached to the image forming apparatus main body, and restores the previous operation mode before switching when a predetermined validity condition has fulfilled.