The invention relates to a voltage monitoring method based on big data processing. A data acquisition system, a basic data platform and a voltage quality correlation index system are included. The data acquisition system is in butt joint with the DMS system and the EMS system through corresponding interfaces; The data acquisition system comprises a voltage monitoring system and a power utilizationinformation acquisition system; And the PMS uploads the acquired connection relationship between the power supply network model and the equipment to the basic data platform through the data acquisition system. The basic data platform classifies and stores topological information, static equipment parameters and historical operation data acquired from the data acquisition system according to a unified modeling principle; An original data maintenance tool is provided, and management and maintenance of the platform are facilitated; The quality of the data source is evaluated, and data credibility and system availability are provided; And basic support services are provided for upper application services. And the voltage quality correlation index system constructs a voltage quality correlation index and sets the voltage quality correlation index as an evaluation index or an assessment index according to requirements.