This work describes a geographical information system (GIS)-based information flow for a land-use zoning review process. GIS technology is employed not only to edit and display maps as conventional GIS applications, but also to enhance work quality. These enhancements include an exploration of hidden information, the production of tentative zoning maps, recognizing potentially problematic areas, conducting crucial site investigations, facilitating informative public hearing, and presenting potential policies. In the case of the Yang–Ming–Shan (YMS) National Park, Taiwan, a GIS-based information flow is employed to assist in the land-use zoning review process. This GIS-based information system reveals several features including: (1) a new, more complicated and effective information flow; (2) close coordination of computing and noncomputing sub-processes; (3) prior identification of over and under-regulated areas to avoid potential appeals and conflicts; (4) economical and effective site investigations, and (5) potential policies established for both private and public land. The case of the YMS National Park is encouraging. We believe that the application of a GIS-based information flow is beneficial to both the zoning plan production and the review process.