Abstract: Distribution system is the most important segment of power supply for urban and rural users. Since the 14th Five Year Plan, the cumulative investment in the distribution system has reached trillions of yuan. How to improve the power supply capacity of the distribution system more economically is an important proposition. Per-household capacity directly reflects whether the power supply capacity and carrying capacity of the region are sufficient. For the problem of selection of per-household capacity, a new model for evaluating the reasonable value of per-household capacity is constructed, taking into account factors such as different regional load types, economic development, simultaneity and correction coefficients. A method for evaluating the reasonable value of per-household capacity is proposed and validated through actual data from multiple regions.The results indicate that the method proposed in this paper can effectively guide the planning, design and technological transformation of new distribution systems, thereby providing support for the transformation and upgrading of the traditional distribution network to a new distribution systems.