The invention relates to a method for producing amino- or hydroxybenzonitriles during which, within the scope of an ammonolysis, the corresponding amino- or hydroxybenzoic acid compounds are reacted with ammonia in the presence of a phosphate-containing supported catalyst at temperatures between 250.degree. C. and 500.degree. C. The production step is carried out in a reaction gas without an organic solvent followed by at least a 2-stage purification step.