The invention discloses a voltage regulating system and method. The system comprises a transformer which is connected to a power transmission line and used for adjusting the voltage supplied by the power transmission line to a first preset voltage, wherein the first preset voltage is less than the voltage supplied by the power transmission line; and a frequency converter which is connected with a transformer and is connected to load equipment, wherein the input of the frequency converter is the first preset voltage, and the output of the transformer is a second preset voltage. The second preset voltage is the supply voltage for the load equipment, and the voltage supplied by the power transmission line is higher than a third preset voltage. According to the invention, the system solves a problem that a frequency converter cannot meet the requirements of the load equipment for a high rotating speed.