The invention provides a method for reducing and smelting titania slag by utilizing vanadium-titanium-iron ore concentrates in a molten state. The method comprises the following steps: mixing the vanadium-titanium-iron ore concentrates with titanium ore concentrates and adding a carbonaceous reducing agent and a binder, thus forming a mixture; reducing the mixture and then performing slag-iron separation treatment, thus obtaining semisteel and titanium slag; and spraying water to the surface of the titanium slag obtained through slag-iron separation treatment so as to rapidly cool the titanium slag to 600-850 DEG C in a cooling process, thus forming the acidsoluble titania slag. The method provided by the invention can be used for efficiently utilizing the Fe and TiO2 in the vanadium-titanium-iron ore concentrates and has the advantages of stable molten-state reduction process, good effect in smelting and separating process, stable furnace condition, short smelting period, low power consumption level, low production cost and the like.