Abstract
Estimating population for urban comprehensive plan is a very important work because projecting future population size is a key to landuse and urban infrastructure plan. Overestimating population size causes land overuse and this in turn, leads to development with over density. In this context, this study aims to develop alternative method to estimate population size with close consideration of inmigration effect of development project. For this purpose, this study used alternative method to estimates population increase from various types of development project in Kyeonggi Province since 2005. Result shows that projected population size used in comprehensive plan has been over-estimated. And inmigration ratio varies depending on types of development projects and on location of projects. Residential land development project showed the highest inmigration effect, indicating that more elaborated population estimate is necessary for comprehensive plan.