Image forming apparatus

An image forming apparatus, comprising:

• an image forming unit configured to form an image on a sheet;
• a bookbinding unit configured to perform bookbinding of a sheet bundle including a plurality of sheets;
• a cutting unit configured to cut a predetermined side of the sheet bundle formed by the bookbinding in the bookbinding unit;
• a waste box configured to collect cutting waste produced by the cutting;
• a detector configured to detect a fully loaded state of the waste box, which corresponds to collection of a predetermined amount of the cutting waste in the waste box;
• and
• a controller configured to:
• control, when an order of the sheet in the sheet bundle, on which the image is to be formed, is smaller than a predetermined order, the image forming unit to not perform interruption of image formation processing which is due to detection of the fully loaded state of the waste box detected by the detector, and;
• control, when the order of the sheet is the predetermined order, the image forming unit to interrupt the image formation processing in accordance with the fully loaded state of the waste box, which is detected by the detector.