Abstract: In order to deal with optimal decision problem of engineering project group with interactive coupling correlation among sub-projects, the positive and negative ideal reference points are determined by the normalized decision matrix based on prospect theory. Based on the vertical distance, the prospect value of each alternative engineering project group under a single criterion is calculated, a nonlinear programming model is built to maximize the sum of the comprehensive prospect value of all the alternative engineering project groups to determine the weight of each criterion. The ranking of alternative engineering projects is selected based on improved TODIM method and according to the total superiority degree. Through sensitivity analysis and comparative analysis, the influence of different parameters on the ranking results is discussed, to illustrate the effectiveness and feasibility of the decision making method.