An inorganic oxide powder is produced by a method which comprises a step of (i) introducing, into a dry-way pulverizer, an inorganic oxide in an amount of 100 parts by volume and air, nitrogen or a gas mixture thereof in an amount of from about 25,000 to about 160,000 parts by volume to pulverize the inorganic oxide by the dry-way pulverizer, or (ii) introducing, into a medium-stirring-type pulverizer, an inorganic oxide with a BET specific surface area of from about 1 to about 70 m²/g to pulverize the inorganic oxide by the medium-stirring-type pulverizer in a dry way at a specific energy consumption of from about 0.3 to about 1 kWh/kg. The inorganic oxide powder is capable of providing a ceramic with high density and high mechanical strength.