A multi-objective planning method for distribution networks, which considers demand response and network reconfiguration, was proposed to address the issues of decreased voltage stability, increased network losses, and increased wind and solar power curtailment resulting from large-scale renewable energy integration. First, the structure and operational principles of replacing the original tie-line switches with soft open points (SOP) in the distribution network were analyzed and modeled. Second, a multi-objective mathematical model was established, aiming to maximize voltage stability, minimize planning costs, and reduce operational losses. Then, an improved arithmetic optimization algorithm was introduced to solve the multi-objective model, which was characterized by fast solving speed and high accuracy. Finally, simulations were conducted on the IEEE 33-node distribution system. The results demonstrate that the proposed approach enhances voltage stability while reducing network losses and renewable energy curtailment. Comparative analysis with other algorithms confirms the superior performance of the proposed method. In summary, the multi-objective planning method for distribution networks proposed, which takes into account demand response and network restructuring, can effectively address the operational challenges posed by the large-scale integration of renewable energy into distribution networks, thereby providing a viable planning solution for the safe, economical, and efficient operation of distribution networks.