The invention discloses a method for extracting vanadium from a high acid leaching solution of vanadium slag. The method comprises the following steps that (1) an oxidizing agent is added into the vanadium-contained high-acid leaching solution, stirring is carried out, and the material potential is 1000-1500 mV; (2) an oxidized leaching solution and an extraction organic solution are mixed, and 1-4-stage extraction is carried out so as to obtain a loaded organic phase and raffinate; (3) reverse extraction is carried out on the loaded organic phase by using a sodium carbonate solution; (4) sulfuric acid is added into a reverse extraction solution, then ammonium chloride is added, and a solid-phase precipitate is calcined so as to obtain vanadium pentoxide; and (5) NaCl is added into the raffinate, the pH value is adjusted by using acid, and iron is extracted by using a TBP kerosene extractant. The method has the advantages that the problems that a traditional acidic organophosphorus extractant is large in acid and alkali consumption and long in flow path in the vanadium extraction process can be solved, the purpose of efficient synergistic extraction of the vanadium in the high-acidleaching solution is achieved, and the high-purity vanadium pentoxide is obtained in the subsequent alkaline reverse-extraction, direct vanadium precipitation and roasting processes.