According to the characteristics of distribution network and distributed generation，this paper establishes a multiobjective optimal model by minimizing the distribution network loss，distributed power costs and maximizing voltage stability. A multiobjective particle swarm optimization algorithm based on improved adaptive weight strategy for optimizing DG configuration is proposed. Compared with traditional multiobjective algorithms that are readily trapped at the local minimum, it guarantees to provide an solution closer to the global minimum. Meanwhile the algorithm offers a series of alternative solutions in better fitness to the Pareto optimal boundary in comparison with singleobjective algorithms. Finally, a numerical example of an IEEE 69bus system is employed to verify the reliability, adaptability and practicability of the proposed algorithm.