This study developed a GIS-based suitability assessment model of coastal zoning system that is needed in the substantial classification of coastal zoning system according to the establishment of law about coastal zoning system. First, this study investigated several kinds of regulations, GIS database and application system related coastal area. Also, grid data model was selected as the GIS analytical model for calculating items of suitability assessment of coastal zoning system. And Grid-based analytical method was suggested for calculating items composing of sea and spatial location characteristics including physical one. Critical values of items were presented using standards that were suggested in coastal regulations and land suitability assessment. Especially, this study presented a calculation method of continuous pattern as fuzzy set function for reflecting the characteristics of GIS data. And this study classified the suitability grade using Z-score and developed model designating coastal zone as conservation management priority, utilization management priority, and planning management priority. This study is judged that very efficient business performance is possible if we consider the spatial coverage of study area and GIS database when the suitability assessment model of coastal zoning system that is suggested in this study, is applied to business works.