Rapid urbanization development often leads economic convergence,frequent social network linkage and attract people towards urban concentration. This may cause overloaded environmental problems,destruction of urban life support systems, and degradation of life quality.Furthermore, the impact of global environmental problems, such as greenhouse effect, acid rain, dust storm, etc., has already stimulated awareness of environmental conservation and to carry out regional development planning. Urban cities, therefore, play an important role in sustainable development. The establishment of the eco-city index is crucial in developing sustainable eco-city strategies.The selection principle of eco-city index is determined initially based on the definition of eco-city found in the literatures. Candidates for eco-city indices are then established. To increase the objectivity of the eco-city planning strategy evaluation factor, the Fuzzy Delphi Method (FDM) is used to sieve through all the potential eco-city indices to esablish the best representative indices. The Analytic Hierarchy Process (AHP) is then used to calculate the weight of the indices to increase its reliability. As a result, experts agree that environmental ecology is the top priority index, followed by education and culture, economic development,society security, and metabolic cycling. The composite eco-indicator is calculated according to the weighing given to different indices. The composite indicator is compared at several potential cities to provide useful guidance and strategies for future sustainable urban development.