For the impact of more and more PV distributed access to the distribution network on the voltage stability of the system, the mechanism of the impact of PV distributed access on the voltage stability of the distribution network is analyzed. By calculating and analyzing the voltage stability of PV access to the distribution network under different locations and weather conditions through actual system calculations, an IEEE7 node simulation model of distributed power access to the distribution network is established, and the voltage fluctuations of the distribution network under different access capacities and different access points of distributed power are simulated and analyzed, and the influence law of distributed power access to the distribution network voltage fluctuations is obtained. The research results in this paper can provide effective theoretical reference and technical guidance for the access of distributed power sources in distribution networks.