The invention relates to the technical field of 
metallurgy, and provides a composite additive used for 
roasting vanadium extracting. The additive is formed through the step that four materials including, by 
mass part, 35 parts to 55 parts of 
sodium materials, 15 parts to 25 parts of 
calcium materials, 0.5 part to 1 part of 
vanadium materials and 1 part to 5 parts of 
titanium materials are mixed and ground to 80 meshes to 100 meshes; the invention further provides a use method of the composite additive used for 
roasting vanadium extracting. The use method comprises following steps: A, mixing, wherein screened vanadium containing raw materials are selected, and a mixed material with the evenly-mixed composite additive is added; B, 
roasting, wherein the mixed material is subject to two-time roasting. According to the composite additive and the use method of the additive, the vanadium-contained ore is not likely to generate a 
liquid phase in the roasting process, the phenomenon of equipment bonding is avoided, toxic and harmful substances are not likely to be generated, the conversion rate and the purity of vanadium can be effectively improved, the roasting time is shortened, the roasting process is simplified, production cost is reduced, and 
process efficiency is improved.