The invention relates to an image forming system and control method. In a case where conveyance abnormality of a sheet has occurred on a conveyance passage in course of execution of a print job which uses sheets included in a sheet set including a plurality of sheets with sequentiality stored in a first sheet feed tray(161) and discharges a sheet having been subjected to image formation to a first discharge section(491) of the plurality of discharge sections, conveyance of a causal sheet having caused the conveyance abnormality is stopped, and sheets having been being conveyed on the conveyance passage on an upstream side than the causal sheet are discharged to other discharge section(492) other than the first discharge section. Thereafter, continuously, sheets located before a sheet to be fed first at a time of performing recovery printing after elimination of conveyance abnormality, are fed from the first sheet feed tray, and discharged the sheets to the other discharge section(492).