The invention provides a voltage security pre-warning, prevention and control system based on multiple information sources. The voltage security pre-warning, prevention and control system comprises a human-computer interface subsystem, a system managing and maintaining subsystem, a data communication subsystem, a dynamic data processing subsystem, an online parallel computing subsystem, an online voltage security evaluation subsystem and an online prevention and control subsystem. With the adoption of the voltage security pre-warning, prevention and control system based on the multiple information sources, the online application of a whole process dynamic simulation tool is realized; the time scale of anticipated accidents and the simulated analysis depth are expanded through combination of quiescent voltage stability analysis and transient voltage stability analysis, and in consideration of responding-based voltage stability analysis; pre-warning is given to the possibly occuring problem of voltage instability according to a whole process evaluation result of the online voltage security; and rapid and effective preventive control measures or optimizing strategies are given to an operation mode that the stability margin of the voltage security is in shortage, so that preventive control and emergency control of the online voltage stability are realized, and the power outage caused by breakdown of the network voltage is avoided.