The invention relates to a coal additive for coal-fried boilers in industries such as electricity generation, thermoelectricity, petroleum, chemical industry, metallurgy and the like and particularly relates to a boiler chromium-based decoking and coal saving agent composition, which is prepared from the following components in parts by weight: 65-80 parts of chromium oxide, 12-20 parts of copper sulfate, 8-13 parts of cerium oxide, 8-13 parts of vanadium pentoxide, 10-16 parts of manganese dioxide, 12-18 parts of potassium permanganate, 6-11 parts of potassium chlorate, 15-22 parts of zinc oxide, 10-15 parts of potassium molybdate, 8-13 parts of cobalt carbonate, 9-15 parts of barium carbonate, 30-40 parts of sodium carbonate, 6-10 parts of ferric trichloride, 40-55 parts of active white attapulgite clay and 0.1-0.3 part of a penetrant JFC. By using the boiler chromium-based decoking and coal saving agent composition, the problems of boiler coking and dust deposition, which are not solved for a long time, of the coal-fried boilers, are solved, the coal saving rate is larger than 4%, the problem that boiler parts are corroded by acidic substances is solved, the service life of a boiler is prolonged, and the atmospheric environment pollution is reduced. The boiler chromium-based decoking and coal saving agent composition is also suitable for deslagging of the coal-fried boilers.