The invention discloses a method for extracting vanadium from molten iron. The method comprises the following steps: contacting the molten iron with a desulfurizer, separating out the generated slag to get the desulfurized molten iron, and oxidizing the vanadium (V) in the desulfurized molten iron to vanadium pentoxide, wherein, based on the total mass of the molten iron, the molten iron comprises 0.23-0.34wt% of V and 0.04-0.15wt% of S, and the content of sulfur (S) in the desulfurized molten iron is not more than 0.02wt% due to the condition of contacting the molten iron with the desulfurizer; and the desulfurizer comprises Na2CO3, CaO and CaC2, and based on the total mass of the desulfurizer, the content of the Na2CO3 is 2.5-6wt%, the content of the CaO is 69-87.5wt% and the content of the CaC2 is 10-25wt%. By utilizing the method provided by the inventionthe sulfur is ensured to be removed from the molten iron, silicon can be removed from the molten iron to the maximum, and the loss of vanadium is reduced to the minimum at the same time, thereby greatly improving the grade of the vanadium slag and the recovery rate of vanadium during extracting the vanadium.