A process for producing aluminum nitride includes a nitrogen occluding step and a nitriding step. In the nitrogen occluding step, nitrogen is occluded in an aluminum powder having an average particle diameter of from 10 to 200 m by holding the aluminum powder in a nitrogen gas atmosphere of 460 C. or more for 10 minutes or more. In the nitriding step, the aluminum powder with nitrogen occluded therein is nitrided by developing a nitriding reaction at a temperature of from 500 to 1,000 C. while holding the aluminum powder in a nitrogen atmosphere whose nitrogen gas pressure falls in a range of from 80 to 300 kpa. Thus, aluminum nitride, in which aluminum is inhibited from remaining and which has small particle diameters, is calcined at a lower temperature and is actively used to make high-quality substrates, can be produced at a lower temperature with a high yield.