Abstract: A mathematical model is developed to analyze numerically coal pyrolysis and heat transfer inside a heated coal particle.Endothermic effect of decomposition and transpirational convective heat transfer are taken into account.A coupled comprehensive model was validated with experimental data of pulverized coal and large particles.Then,temperature history and coal pyrolysis of coal particle heated were analyzed numerically.Effects of endothermic of pyrolysis,transpirational convection,volatile content and particle size were investigated to understand physically transient temperature and volatile evolution of coal particle.