The invention discloses an energy-saving modification method for a hot rolling high-pressure water scale removing system based on an energy accumulator and a high-voltage inverter. The method includes the following specific steps that firstly, the energy accumulator is selected according to the scale removing water consumption in a rolling period; secondly, the high-voltage inverter is selected according to the speed increase and decrease time of a scale removing pump and the rotational inertia of a motor; thirdly, the energy accumulator, the high-voltage inverter, the scale removing pump and the motor are connected and matched; and fourthly, the scale removing pump provided with the energy accumulator and the high-voltage inverter is put into production and use, and energy is saved. The method has the beneficial effects that the high-voltage inverter combined with an energy accumulator system is adopted as an energy-saving modification main device, the high-voltage inverter can use the scale removing interval for speed reduction to achieve energy-saving modification, the purposes of energy consumption reduction, energy conservation and emission reduction can be better achieved on the premise that the requirements of the production technology are met, and a whole energy-saving modification system with the high-voltage inverter and the energy accumulator is formed.