An image forming system includes an image forming apparatus configured to form an image on a sheet, a plurality of accessory apparatuses arranged side by side along a conveyance direction of the sheet, and a base station configured to wirelessly communicate with the image forming apparatus and the plurality of accessory apparatuses. The image forming apparatus includes one or more controllers configured to function as (i) a unit configured to acquire, from the base station, information that the base station acquires by wirelessly communicating with the plurality of accessory apparatuses, and (ii) a unit configured to output screen information for registering information about an arrangement order of the plurality of accessory apparatuses, based on the information acquired from the base station.