A three-hierarchy supply chain coordination model under the fuzzy demand environment was set up by means of bi-level programming. The supply chain system consisted of multiple suppliers, one manufacturer and multiple retailers. According to the internal form of the model’s constraints, Chaos Search algorithm was applied to solve the model and an example was cited to verify the feasibility of the model. The numerical results have shown that the core enterprise manufacturer can coordinate the interests among the supply chain members by applying the strategy of coordination development with its suppliers and price discount with its retailers, thus, realizing the Pareto improvement. And the research can provide a basis for the supply chain decision-makers under the fuzzy demand environment.