The invention relates to the field of thermal power generation, and discloses a coal combustion system capable of realizing near zero emission of atmospheric pollutants. The coal combustion system comprises a boiler (10), a denitration device (30), a desulfurization device (70) and a flue gas exhaust cooling tower (90) which are arranged in sequence, wherein a combustor of the boiler (10) is an air gradation low-nitrogen combustor. According to the coal combustion system disclosed by the invention, the production of nitric oxide is controlled from the combustion source through the air gradation low-nitrogen combustor, denitration treatment of the denitration device and desulfurization treatment of the desulfurization device are combined, and meanwhile, a flue gas exhaust mode of the flue gas cooling tower is adopted, so that the near zero emission of the atmospheric pollutants can be effectively realized under the combined action of the denitration device, the desulfurization device and the flue gas cooling tower.