Under the influence of the reform of transmission and distribution price, the profit model and operation mode of power grid enterprises have undergone major changes. It is urgent to transform the operation concept and investment decision of enterprises. The reformed power grid investment demand and investment capacity coordination optimization model provides a direction that can be optimized for power grid investment decision-making.Firstly, the investment demand of the power grid is analyzed, and the power grid investment capacity is devided into distributable profits, financing funds, and depreciation costs, and then a power grid investment capacity calculation model based on the transmission and distribution price reform is built. Then the coordination coefficient of power grid investment capacity and investment demand is calculated, considering multiple constraints, an optimization model of power grid investment demand and investment capacity is established, and particle swarm optimization algorithm is introduced for coordination optimization. Finally, simulation analysis is carried out considering whether the investment demand and investment ability are coordinated, and the corresponding investment management strategy is proposed according to the simulation results. The verification of the example shows that the model can provide a more effective reference for power grid enterprises to formulate a reasonable investment plan.