In this presentation, an improved kinetic model has been proposed which improves understanding of mechanisms involved in ISC process. Light oil component defined in this model is actually the light hydrocarbon distilled or cracked from original oil at low temperature condition. The experimentally obtained temperature profiles and produced gas composition have been reasonably matched based on the improved model. Coke is not the unique fuel in this experiment. The other sources of fuel would be distilled hydrocarbon and cracked hydrocarbon. Oxygen concentration and flow flux are important parameters which can affect combustion behavior significantly.