This work aims to investigate numerically the catalytic combustion of a catalytically stabilized combustor. The numerical model treated a catalytic channel deposited with Pt and used a plug model of laminar, one-dimensional, and steady-state how. The predicted conversions of mixture and ignition temperatures of surface reaction agreed well with the measured data when a multi-step mechanism was used for the CH4 surface reaction over Pt. The flame speed of a mixture supported by catalytic surface reaction was found to increase compared with a mixture without a catalytic combustion. CO mole fractions were analysed for three cases-gas reaction, surface reaction, and gas reaction coupled with surface reaction. The case of solely gas reaction produced the most CO emission and the case of solely surface reaction generated the least CO emission. The position where flame ignites was also evaluated numerically. There was only a small difference between the measured and predicted results on the starting points of flame in the catalytic channel. As a result, the plug model was shown to model surface ignition very well, however, it did not predict well the position of flame ignition. Copyright (C) 2000 John Wiley & Sons, Ltd.