Abstract: With the increasing proportion of new factors, such as distributed generation and electric vehicles connected to the power grid, the field of distribution networks is becoming increasingly complex. A secondary system must be constructed for a distribution network that can adapt to the construction demands of a new power system to enhance the local autonomy and fault self-healing ability of the distribution network. First, the challenges faced by the development of distribution networks in the new situation are analyzed, and the current development status and existing problems of the existing secondary systems of distribution networks are summarized from four aspects: data acquisition, transmission, storage, and application. Then, to address the problems in various aspects of the secondary system of distribution networks, a development strategy of “controlling the middle and letting go of both ends” is proposed. The future architecture of each aspect of the secondary system of distribution networks is discussed, providing a reference for their construction under the new power system.