Production of biodiesel, as a substitute for petroleum, has been growing dramatrically due to the government supportive policy in Korea. However, concerns over increasing import of feedstock for producing biofuel limit the deployment policy. This study aims at deriving main determinants in the decision process of biodiesel and its feedstock investment. The development of feedstock plantation for biodiesel can reienforce the supportive policy of biodiesel. As a methodology, analytic hierarchy process (AHP) was adopted to extract major decision factors. Based on questionaires on 8 biodiesel companies, the analysis shows production costs and cultivated area of oilseeds are considered as most important factors in the decision of biodiesel investment. Among indirect factors, moral decaying index is regarded as the most important factor. The application to Latin America countries shows that Brazil and Arzentina are the most attractive countries for biodiesel investment.