The construction of traditional large-scale central power plants and the extension of power lines in Taiwan have tremendous difficulties in terms of the land acquisition and environmental protection. In addition, one potential risk of energy supply is that over 95% of energy source is imported overseas. Therefore, the most important goal of Taiwan energy policy is to cut down the amount of energy import. To achieve the goal, it is important to explore innovatively local energy source by developing the renewable energy. Among the available renewable energy technologies, the technology of wind power is the most well developed one besides the hydraulic power. Because of the limited land resources and restrictive regulations, it is expected that wind farm development in Taiwan can only be set up in offshore, instead of inland. In the present study, we propose a multi-functional wind farm site, which involves ocean farm ranch. This may be desirable to bring mutual benefits for both developers and local stake holders. The present study has analyzed the diverse aspects of offshore multi-functional wind farm development under the framework of Integrated Coastal Zone Management (ICZM). From a macroscopic view point, we have considered the environmental impacts of from the wind farm construction, as well an ocean farm ranch operation at the site. The ocean farm ranch included the establishment of offshore cage aquaculture and artificial reef. A hierarchy indicator set has been identified to account for the diverse factors, consisting of marine environment, ecosystem, and social-economy. The cross linkages chains between the interrelated factors have been carefully examined and established using the Integrated Assessment (IA) approach. It is therefore easy for the decision makers to comprehend the complex relations hips common the diverse environmental factors if an offshore multi-functional wind farm is to be developed in the future. The sustainable usage of coastal resource must be achieved for the offshore wind farm development.