The inert alumina ceramic ball is used widely as a catalyst covering or support in reactor or as a tower packing in the fields of petroleum, chemical industry, chemical fertilizer, natural gas and environmental protection. It features the properties of resistance to high temperature and high pressure, low water absorption and with chemical stability, available to withstand the corrosion of acid, alkali and other organic solvents and to endure the variation of temperature in the process of production. Its main functions are to increase the gas or liquid distribution range and to support or protect the low-strength active catalyst.