PURPOSE: To easily produce phenol and aniline from inexpensive general raw materials in one step by carrying out vapor-phase catalytic reaction of benzene, water and ammonia in the presence of a catalyst.

CONSTITUTION: The objective compounds can be produced by using benzene as a raw material and reacting with water and ammonia in the presence of a catalyst in an inert gas atmosphere (e.g., nitrogen, helium, argon or carbon dioxide gas atmosphere) under normal or positive pressure at 200-600°C, preferably 300-500°C. The catalyst is those containing phosphoric acid or its salt and is produced e.g., by dissolving a metal salt such as a copper salt in water, adding phosphoric acid or a solution containing phosphoric acid to the salt solution, adjusting the pH of the mixture to 5-7 with ammonia, etc., stirring and filtering the mixture, calcining, crushing and granulating the precipitate, adding usually silicon oxide to the granule as a binder and granulating, drying and calcining the product. The amounts of water and ammonia are ≥1mol per 1mol of benzene.