Static voltage stability of distribution networks will be impacted after the connection of distributed generation (DG) sources. The IEEE 33-nodes test system and Matlab simulation software platform are used and four impacts factors including the number of DGs, their locations, access capacities and power factors are considered. Based on thevoltage stability assessment index L, two cases, which one is a single DG connected to single feeder bus and another is multiple DGs connected to multiple feeder buses, are compared to get their influence on voltage distribution and stability respectively. Compared index L from test, it shows that multiple DG connected to multiple feeder buses is more beneficial to voltage stability of distribution networks. The research is of guiding significance to the layout and planning of multi-DGs in distribution network.