In two component mounting lines or more each including the plurality of the component mounters, a set-up changing work time, necessary for executing set-up changing work in the two component mounting lines or more based on the number of workers assigned for production in the two component mounting lines or more in each time zone, and the number of workers necessary for the set-up changing work necessary when the mounting board is changed in the two component mounting lines or more, is calculated; and a production completion time, which includes a set-up changing work time and at which the production of all the mounting boards that are the production targets is completed, is calculated; and a group is determined so that the production completion time is shortened within a predetermined time period in the two component mounting lines or more.