The invention discloses an electrolytic preparation method of vanadium-aluminum alloy. The method comprises the following steps that A, vanadium pentoxide, aluminum oxide, binding agents and addition agents are mixed evenly, pressed and formed by a press, dried, and sintered at a high temperature to obtain a solid cathode block; B, a graphite block serves as an anode, mixed fused salt of sodium chloride and calcium chloride serves as an electrolyte, and fused salt electrolysis is conducted; and C, after fused salt electrolysis is completed, the cathode block is lifted out of the fused salt, washed, dried, refused in the inert atmosphere, and finally taken out of a furnace to obtain the vanadium-aluminum alloy. The defects that procedures are complex and the impurity content is high in the prior art are overcome, and the electrolytic preparation method of the vanadium-aluminum alloy has the advantages of being simple in raw material procedure and low in energy consumption.