The utility model discloses an all-vanadium redox flow battery which comprises a negative electrode electrolyte storage tank, a positive electrode electrolyte storage tank, a negative electrode, a positive electrode, an ion exchange membrane, a first pump, a second pump and a load, wherein the negative electrode electrolyte storage tank, the negative electrode and the first pump are connected in series, the positive electrode electrolyte storage tank, the positive electrode and the second pump are connected in series, and the ion exchange membrane is arranged between the positive electrode and the negative electrode; the all-vanadium redox flow battery is capable of realizing charging and discharging of electric energy by virtue of the mutual transformation between the redox couples of different valence state of the vanadium ion in the liquid storage tank, the all-vanadium redox flow battery is a unique electrochemistry energy storage system which is composed of the same element, and the condition that the different types of active materials in the positive electrode and the negative electrode permeate and pollute each other is avoided, so that exploding is not caused; the electrochemical polarization of the all-vanadium redox flow battery is less, and the battery is capable of realizing large current charge and discharge. The all-vanadium redox flow battery completely meets the technical requirements of the wind energy power storage systems on the aspects of service life, efficiency, cost and safety.