Electric mechanism reform has put forward strict requirements on the accounting of transmission and distribution prices. To achieve the dual carbon goal, it is necessary to increase the proportion of investment in supporting projects for distributed energy generation. How does the power grid investment strategy affect the transmission and distribution price under dual pressure need to be studied urgently. Through differentiated analysis of the main parameters affecting power grid investment, including the effectiveness of investment scale, investment structure and investment timing, a differential grid investment and transmission and distribution price linkage model is constructed based on the SD platform, and four different investment scenarios are set based on the influencing parameters to calculate the transmission and distribution price. The calculation example results show that investment constraints will lead to the calculation result of transmission and distribution price is significantly smaller than the conventional result, and the adjustment of investment scale, investment structure and investment timing will affect the transmission and distribution price to a certain extent. Among them, the efficiency variation of investment scale has the greatest impact on transmission and distribution price, while investment timing has the least impact.