The invention relates to an improvement of a fire coal combustion improver. The improved fire coal combustion improver is characterized by being prepared by compounding and mixing the following components: 20 to 30 weight percent of dolomite powder, 5 to 15 weight percent of dicyclopentadieny iron, 3 to 10 weight percent of chromium trioxide, 3 to 10 weight percent of manganese dioxide, 3 to 15 weight percent of magnesium nitrate, 3 to 15 weight percent of sodium dichromate and/or potassium dichromate, 3 to 18 weight percent of zinc oxide, 15 to 30 weight percent of active clay. The fire coal combustion improver has a plurality of functions of combustion acceleration, sulfur solidification, smoke abatement and the like; the thermal efficiency of a boiler can be improved by 3 to 8 percent; the coal-saving efficiency is up to 5 to 15 percent; the Ringelmann smoke blackness is less than 1; the total removal rate of SO2, NOx and the like is 25 to 60 percent, and the combustion improver has remarkable coal-saving and environmental-protection effect. Since the combustion effect is improved, the inferior coal (such as coal gangue), which is difficult to combust normally, is combusted and comes into play. After the long use, the boiler is not corroded, the scaling of the calcium sulfate in the boiler can be reduced, the operation safety of the boiler can be improved and the service life of the boiler can be prolonged.