A method for producing a catalyst containing at least molybdenum, bismuth and iron including the steps of kneading particles containing catalyst components, an organic binder and a liquid, where the organic binder contains at least a high-viscosity organic binder having a viscosity of from 5,000 mPas to 25,000 mPas and a low-viscosity organic binder having a viscosity of from 10 mPas to less than 5,000 mPas, and extrusion molding the resultant kneaded mixture is provided.