The present invention provides a technique that can prevent an increase in power consumption due to intermittent execution of print jobs with low execution priorities and contribute to a reduction in CO.sub.2 emission. The technique is to discriminate content of a received print job, cause a storage medium to temporarily store, in a predetermined storage area, a print job discriminated as having first content with a low execution priority and cause an image forming apparatus to execute, together with the print job having the first content stored in the predetermined storage area, a print job discriminated by the job discriminating unit as having second content that should be more preferentially executed than the first content.