Vanadium pentoxide series of sulfuric acid catalysts can be used in the process of sulfuric acid production, to be more specific, is the process of SO2+I/2O2---SO3. With the help of Vanadium Catalyst, the rate of conversion can be improved greatly. It can guarantee the air speed of operation to add 10-20% more when using type star ring catalysts or ring catalysts. Vanadium catalyst can be applied in many fields, such as, sulfur-based acid production, pyrite-based acid production, nonferrous smelting gas-based acid production, gypsum-based acid production etc.