As the low-cost carriers of the region enters the air transportation market, the domestic air transport circumstance is to be changed and each local autonomous entity conducts the feasibility study to develop the regional airport. But the airport is developed almost all by the goal of the policy and actually the valid basis of the airport development is often weak. To present the validity of the regional airport development Using the pre-feasibility study method the government performs I apply it to the airport development project of the Seo-san region. To present the validity of the regional airport development this study carries out the pre-feasibility study by the AHP analysis.