The invention discloses an energy conservation potential evaluation method for power grid contract energy management projects. Firstly, a typical energy conservation scheme library including operation parameters of all power grid devices in the contract energy management projects is built; then, each power parameter of each power grid device in a to-be-reformed project is acquired; according to the each power parameter during operation of each power grid device, initial selection is carried out on each power grid device, power grid devices with energy conservation potentials are selected, a power grid with a large energy conservation potential is selected to be substituted to the typical energy conservation scheme library, and an energy conservation quantitative diagnosis model is generated; and finally, according to the energy conservation quantitative diagnosis model, energy conservation benefit comprehensive analysis is carried out on the power grid devices, and a project with a large energy conservation potential is selected as the energy conservation prophase project. The method of the invention can be applied to various change conditions of an energy consumption unit, an energy conservation potential evaluation result can be given more quickly and reasonably, and the service risks of an energy conservation service company are reduced.