Although sustainable ecotourism has been developing for years, most people still travel purely for sightseeing, not ecotourism. The study applied Contingent Valuation Method (CVM) to analyze the non-use economical benefits of the ecological resource on the Lanyu from the very first of this research, and then applied the SWOT analysis to develop the strategies on Ecotourism. Finally, the research applied the Analytic Hierarchy Process (AHP) to evaluate the strategies and provide the basis of the priority actions to policymaker. The results of this study included: (1) the research indicated that the visitors were willing to pay 785.558 NT dollars per year per person for the resource conservation on Lanyu. The total economical benefits are 45,051,751 NT dollars and this datum also could regard as the funds of ecological conservation applying from the government. (2) The strategies of ecotourism in the future are in sequence: (i) invite the professionals to set up the plans of conservation and integration on Lanyu; (ii) set up the visitor center, offer the interpreter and exhibit the agricultural products; (iii) proceed the control of carrying capacity for the sustainable development on ecology industry; (iv) build the exclusive exhibition and website to display the database of ecological conservation; (v) found the authority institution.