This study focused on the “Underused Land Right Establishment Promotion Plan System” for promoting the use of underused land and “Commons Agreement” for creating public space by consolidating underused land. By questionnaires and interviews with local governments and private organizations, to identify issues or barriers to the utilization of these systems. As a result, the local government recognized that planning efforts, especially consensus building with landowners, was a challenge. To promote the use of low-underused lands, it is necessary to conduct social experiments and other initiatives to help consensus building with landowners. The development of urban areas and the existence of private urban planning organizations are necessary to conclude agreements. Conversion of low-underused lands into public space is likely to be difficult only in locations where there is a high demand from residents due to its low profitability.