To provide a job scheduler, a job scheduling method, and a job control program that are capable of, even with an incapable CPU not equipped with a real-time OS, meeting basic real-time property that is required in a system. The job scheduler is a job scheduler 5 for calling each of a plurality of jobs for controlling an appliance to a main loop and causing each job to be executed. The job scheduler 5 carries out calling control including: dividing the jobs into a plurality of groups according to a degree of need for real-time processing of each jobs; setting a priority on a group basis; and restricting a calling frequency, per cycle, of a job belonging to a group of low priority to a minimum tolerated frequency.