Damage to the natural environment is becoming increasingly complex in modern society, expanding to impact not only the environment but also society and the economy. Various systems and policies based on sustainability have been promoted internationally. Legal systems and policies based on evaluation systems such as land environment assessment and urban ecological status maps, have been implemented in Korea. However, most of Korea institutions and policies related to the natural environment have been directed toward the conservation of the natural environment, and restricted to in simple theoretical frameworks with various limitations. Therefore, this study analyzed the definition and value of the natural environment for a fundamental conceptual approach to the valuation of the natural environment. Based on this, we modeled the policy process for a flexible evaluation system suitable for the actual situation of Korea natural environment through a review of the integration of environmental policy proposed in Europe.