The invention relates to a combustion method capable of effectively reducing slagging of a boiler hearth. Electrical energy is mainly obtained through thermal power generation of fire coal, power coalin China mostly is inferior coal, and slagging of a hearth during combustion is a problem plaguing the running of a power plant for a long time; and at present, a concentrated arrangement manner is adopted for combustors, the combustion temperature of pulverized coal is high, the slagging condition of a water-cooling wall of the boiler hearth is worsened, and the high-temperature corrosion of thewater-cooling wall is intensified. According to the combustion method, from composition, main combustors are comprised, each main combustor comprises a group of primary air nozzles and secondary airnozzles which are arranged at intervals, horizontal concentrated-dilute nozzles are selected as the primary air nozzles, the spiral directions of the secondary air nozzles are parallel to the centralaxes of the combustors, and the sprayed gas flow is parallel to the central axes of the combustor; and the main combustors are installed at the four corners of the boiler hearth, the central axes of the corner combustors and the water-cooling wall of the hearth form included angles alpha, and a small imaginary tangent circle is formed, so that the slagging and the high-temperature corrosion of thewater-cooling wall are effectively avoided. The invention relates to a combustion method capable of effectively reducing slagging of a boiler hearth.