Abstract: Investment optimization according to technological rationality and investment benefit of projects is an critical issue as the huge investment in construction of distribution system. In this paper, an index system is established for quantitative evaluation of construction projects in distribution system from the aspects of technical rationality and economic rationality. Furthermore, a mixed weighting method based on the ahp and entropy method is proposed for comprehensive evaluation of priority of different projects, so a quantitative basis can be provided for investment optimization in distribution system construction.