PURPOSE: To obtain a nitrile useful as an industrial raw material, by reacting a methyl-substituted aromatic compound or methyl-substituted olefin with NO in the presence of an alumina catalyst supporting an alkali metal oxide and tellurium oxide as a catalyst.

CONSTITUTION: A nitrile (e.g. m-phenoxybenzonitrile, acrylonitrile, etc.) can be produced by reacting the corresponding methyl-substituted aromatic compound (e.g. m-phenoxytoluene) or methyl-substituted olefin (e.g. propylene) with nitrogen monoxide in the presence of an alumina catalyst supporting an alkali metal oxide such as Cs2O, Pb2O, K2O, Na2O, Li2O, etc. (0.5W10wt% of the alumina) and a tellurium oxide such as TeO2, TeO3, etc. (5W20wt% of the alumina). The catalyst is effective not only to improve the reaction activity and selectivity of the nitrilation reaction but also to shorten the induction period necessary to stabilize the activity and selectivity.