Abstract: Based on the consideration of the impact of offshore wind farm construction on the safety of ship navigation in the surrounding waters,for the two conflicting objectives of wind energy density and construction cost involved in offshore wind farm siting,this paper objectively evaluates the navigational risk in terms of the natural environment and the traffic environment,and constructs a multi-objective optimization model for offshore wind farm siting with navigational risk as the constraints.The model is solved by NSGA-Ⅱ with elite strategy,and the compromise solution is selected from the Pareto optimal solution set by using the approximate ideal solution ranking algorithm TOPSIS.Taking the sea area within 50 km offshore of the west coast of Hainan Island as an example,the feasibility and effectiveness of the constructed multi-objective site selection model are verified,providing the decision support for the scientific site selection of offshore wind farms.