In the present study, the numerical simulation of reactive turbulent flow and heat transfer in a regenerative gas-fired furnace has been carried out to investigate its performance. The effects of geometric and operating conditions oil the performance of the furnace have also been studied. A moment closure method with an assumed beta probability density function for mixture fraction is used in the present work, to model the turbulent nonpremixed combustion process in the furnace. A comparison is made between the predicted results and the experimental data.