Abstract: In a diffusion-flamelet-based Hencken burner test setup, the flame radiation spectrums and images of bituminous coal particles were measured by the optical fiber spectrometer and CMOS camera under different combustion atmospheres (O₂/N₂ and O₂/CO₂), hot coflow temperatures (1 473-1 873 K) and oxygen volumetric fractions (5%-20%), respectively. The combustion characteristics and temperature distribution of pulverized coal particles were obtained under different combustion conditions. Results show that under O₂/N₂ or O₂/CO₂ atmosphere, the color of flame gradually changes from bright yellow to dark red while the temperature of coal particles decreases with the reduction of hot coflow temperature and oxygen volumetric fraction. The temperature fluctuation coefficient of coal particles could be reduced by 37% with the decrease of coflow oxygen volumetric fraction, indicating more uniform distribution of coal particles. Compared with that in O₂/N₂ atmosphere, the flame intensity of pulverized coal is weaker in O₂/CO₂ atmosphere, with an increased ignition standoff distance of pulverized coal, a decreased average temperature of coal particles by 24-103 K, and a maximumly reduced temperature fluctuation coefficient by 24%.