In an image forming apparatus identifying recording materials to decide printing conditions, information concerning the type of the recording materials identified by a recording material identification unit is stored for each paper feed port. In a subsequent print job to be printed, the use of the information having been stored in advance makes it possible to omit the recording material identification process for the subsequent recording materials. This stored information includes individual information for each recording material and a determined value obtained from a plurality of a plurality of pieces of individual information. Once the determined value is set, the determined value is used thereafter. These pieces of stored individual information and the determined value are initialized when a change of paper or the like is detected at the paper feed port corresponding to the value and to the information.