In recent years, the equipment operation of the distribution network has been getting close to the limit state. Therefore, the problem of voltage stability has appeared in the distribution network gradually. In view of the factor that voltage stability is not considered in most current researchers on DG access to distribution network, a method for determining the location and capacity of DG in the distribution network is proposed, which takes voltage stability problem into account. By improving the traditional voltage stability index, the allowed voltage range of power system is included in the stability assessment index. Based on the comprehensive consideration of voltage stability, network power losses and current margin index, this paper uses TOPSIS method to decide the location and capacity of DG in the distribution network. Compared with the traditional voltage stability index, the rationality of the improved voltage stability evaluation method is verified through the simulation on two-node system example. And the feasibility and effectiveness of DG location and capacity determination strategy are verified through the analysis of IEEE33 node system. This work is supported by National Natural Science Foundation of China (No. 51277134).