Abstract: In conventional arts, migration of jobs that are described in JCL language used in mainframes and the like into various open systems can not be supported. A job network auto-generation apparatus under the first aspect of the present invention includes a job network generation means that creates, from an inputted JCL file, a flow link describing a job-step control flow in a job and script files describing job-steps related to above-mentioned flow link; and a job network output means that creates a job network definition file from above-mentioned flow link and above-mentioned script files.