When a user stands in front of an image forming apparatus, sets originals on an ADF, and depresses a start key, a central control unit effects issuance of a print job, which is to be executed subsequent to a scanner job, on a print control order management table. Then, if print data is sent from a client to the image forming apparatus via an external controller, the central control unit issues as a second print job the print request from the client because the first print job was issued on the print control order management table. The central control unit does not operate a printer unit until the original reading operation by the ADF is finished. The moment the original reading operation by the ADF is finished, the central control unit executes printing by the printer unit on the basis of the read original data. After completing printing of all original data read by the ADF, the central control unit starts the print job sent from the client.