Abstract: A three-dimensional mathematical model has been developed for predicting the transport of mass, energy and momentum in the combustion chamber of a rectangular multi-burner. The turbulence two-equation model and Monte-Carlo method ard used for simulating the turbulence flow and radiative heat transfer, and a combustion model of turbulent diffusion flame is considered. The governing differential equations which are composed of velocity, mixture fraction, fuel concentration, stagnant enthalpy, turbulent kinetic energy and turbulent energy dissipation are solved by tri-diagonal matrix algorithm. The distributions of the temperature of fuel gas and the heat flux of wall are predicted in a coking furnace. A comparison between the calculated and measured results shows that the prediction is successful.