Abstract: The construction of new power systems involves the change in both physical form and production organization relationships. With a large amount of investment, how to ensure investment efficiency will be one of the key problems in the construction of new power systems. At present, great changes have taken place in the form of the power grid side, power supply side, and load side. Clarifying the change in investment structure from the perspective of functionalization is the key to discovering the change law of investment, guiding the efficient investment of funds, exploring and improving the investment efficiency of power grid infrastructure, especially unveiling the evolution law of functional investment structure. First of all, the key factors affecting the power grid infrastructure investment were identified through the system dynamics model, and the interrelation, mutual influence, and dynamic change relationship among the factors were further studied. On this basis, the system simulated the evolution trend of each investment function in the power grid infrastructure investment structure under key scenarios, so as to provide suggestions and data support for the medium-term and long-term power grid investment decision-making of enterprises, promote the optimization and upgrading of power grid infrastructure, and build new power systems with higher quality.