According to the convention on biological diversity, the Ecosystem Approach is a strategy for the integrated management of land, water and living resources that promote conservation and sustainable use in an equitable way. Ecosystem Approach is not a concrete method but a strategy of ecosystem management. Ecosystem Approach provides a science and policy framework which can integrate all kinds of theories and methods to solve the complicated social, economic and ecological problems. The origin and evolution of the Ecosystem Approach concept and its inter-linkage with the ecosystem management are reviewed. And the application of the Ecosystem Approach in natural resource management and river basin management are introduced.