Disclosed are an electrolytic reduction system of a vanadium electrolyte and a method for producing the electrolyte. The electrolytic reduction system includes a separating device and an electrolytic tank. The separating device is configured to separate a mixture consisting of a vanadium pentoxide (V2O5) solid and a sulfate acid solution, thereby obtaining a vanadium solution from a liquid discharging port of the separating device and a vanadium solid from a solid discharging port. The vanadium solution includes pentavalent vanadium ions. The electrolytic tank connects to the liquid discharging port of the separating device to contain the vanadium solution. In the method for producing the vanadium electrolyte, other chemical reagents are unnecessarily to be added into the mixture, and the vanadium solution is subjected to an electrolytic reduction process, such that the pentavalent vanadium ions are reduced to tetravalent vanadium ions and trivalent vanadium ions in the electrolytic tank.