The aluminum-carbon-based long nozzle is a functional original used in thesteel smelting process. Due to the addition of graphite，the service life reduction of the longnozzle caused by the oxidation of graphite should be avoid. Generally，the surface of the long nozzle is coated with a layer containing 20%~30%Al2O3 anti-oxidation coatings to meet the requirement. However，during the smelting process of wire-cutting steel and other special steels，it is necessary to strictly control the content of Al2O3 in the molten steel. Therefore，it is requested to reduce the content of alumina in the anti-oxidation coatings applied to the surfaceof the long nozzle in the smelting process to prepare low alumina content of antioxidantcoatings. This paper was focused on the preparation process of low alumina content coatings foraluminum-carbon long nozzle. Through the adjustment of the coatings composition and theamount of water and the water glass added. The microstructure of the fracture of the sampleafter anti-oxidation experiment was analyzed by using a scanning electron microscope，it is concluded that the coatings based on clay powder，potassium feldspar powder and silica sand as the main raw materials，with incorporation of 10%borax could form a good glaze layer at 800 ℃，while the content of Al2O3 reduced down to 12%，forming a low-alumina coatings； When added with 80%water and 40%water glass，the coatings showed the best applicationperformance and anti-oxidation properties. The coatings and the long nozzle could be tightlyadhered to protect the graphite in the long nozzle from oxidation.