Environmental Impact Assessment(EIA) in Korea has developed as a tool for environmental conservation and decision making since Environmental Impact Statement(EIS) preparation in 1981. For effective implementation of it, we do system development and method enhancement continuously. The recently introduced GIS (Geographic Information System) can integrate geographic and attribute data, which will be applied to scoping, assessment, and alternative assessment, etc. in EIA. This study has three major components. First, it explains building of EIA factors of natural environment, living environment, and socio-economic environment of the study area defined in EIS preparation regulation. Second, the study presents applications of assessment method concerning suitability analysis of landfill site using GIS. Finally, it shows integration of GIS and odor impact assessment. Based on these analysis, the study makes some recommendations and conclusions.