A determination device configured to determine an accommodation plan for accommodating backup pins in a backup pin accommodation section in a component mounter that includes the backup pin accommodation section, a backup pin disposition section, and a moving mechanism, the component mounter disposing the backup pins, being accommodated in the backup pin accommodation section, by moving the backup pins to a board support position on the backup pin disposition section by the moving mechanism, and mounting a component on a board supported by using the backup pins, wherein the backup pin accommodation section is a region where backup pin which is not used for supporting the board is accommodated, and backup pin disposition section is a region where backup pin used for supporting board is installed, the determination device comprising: a job acquisition section configured to acquire a job to be produced for defining a type of the board on which the component is mounted, and a required number of backup pins to be required to support the type of the board; a maximum accommodation number acquisition section configured to acquire a maximum accommodation number of backup pins accommodatable in the backup pin accommodation section in the job; characterized by an accommodation plan determination section configured to determine the number of backup pins to be accommodated in the backup pin accommodation section before starting production of each of multiple acquired jobs to be produced, the determination being made based on the required number of backup pins, which is required in each of the multiple acquired jobs to be produced, and the maximum accommodation number of backup pins accommodatable in the backup pin accommodation section, when a production order of the multiple jobs to be produced acquired by the job acquisition section is determined, wherein the accommodation plan determination section is configured to determine the number of backup pins accommodated in the backup pin accommodation section before the start of production of each of the multiple acquired jobs to be produced so as to minimize the number of times of operations with respect to the backup pin accommodation section, before the start of production of a first job to be produced until end of production of a last job to be produced with respect to the multiple acquired jobs to be produced. a job acquisition section configured to acquire a job to be produced for defining a type of the board on which the component is mounted, and a required number of backup pins to be required to support the type of the board; a maximum accommodation number acquisition section configured to acquire a maximum accommodation number of backup pins accommodatable in the backup pin accommodation section in the job; characterized by an accommodation plan determination section configured to determine the number of backup pins to be accommodated in the backup pin accommodation section before starting production of each of multiple acquired jobs to be produced, the determination being made based on the required number of backup pins, which is required in each of the multiple acquired jobs to be produced, and the maximum accommodation number of backup pins accommodatable in the backup pin accommodation section, when a production order of the multiple jobs to be produced acquired by the job acquisition section is determined, wherein the accommodation plan determination section is configured to determine the number of backup pins accommodated in the backup pin accommodation section before the start of production of each of the multiple acquired jobs to be produced so as to minimize the number of times of operations with respect to the backup pin accommodation section, before the start of production of a first job to be produced until end of production of a last job to be produced with respect to the multiple acquired jobs to be produced.