Abstract: An installation for nitriding-sulphiding of steel and cast-iron articles including an enclosed tank, and a retort containing sulphur and placed in the interior of the tank. The retort is surrounded with a heating device. The tank is provided at its top with two pipe connectors. One connector is connected with the container of ammonia and the other connector is connected with the furnace for chemical and heat treatment of the articles. The ammonia flows from its container to the tank with a retort containing sulphur, wherefrom after being mixed with the vapors of sulphur, it flows out to the furnace in which the articles to be treated are placed. In the furnace at a temperature of 400.degree.-700.degree. C., the nitrogen and sulphur diffuse to the surface layer of the treated articles, thus producing the required sulphides in the nitrided layer.