In recent years, power grid companies continue to increase their investment in distribution network. However there is a lack of a scientific and reasonable investment benefit evaluation system for distribution network projects. In order to solve this problem, this paper firstly constructs a two-level distribution network project investment benefit evaluation index system from the aspects of equipment level, grid structure, power supply capacity, and newly added power supply. Secondly, the analytic hierarchy process and entropy method are used to calculate the weight of each index in the evaluation system. Then the game theory method is used to synthesize the two weights to form the final weight of each index. Finally, the principal components of the evaluation index data of each project are extracted by the nuclear principal component analysis method, and the investment benefits of each project are sorted based on the comprehensive score of the principal components and the investment amount. Numerical simulation examples show this method can scientifically and reasonably evaluate the investment benefits of distribution network projects and effectively guide the construction and transformation of distribution network.