The Fire Dynamics Simulator (FDS) was applied to a center fire in a room, of which dimensions were 1.8m${ imes}$1.38m with an opening of 0.45m${ imes}$1.2m doorway, to evaluate the numerical method. The time-variation of temperature at a top point of thedoorway centerline and distributions of evaluate the numerical method. The time-variation of temperature at a top point of the doorway centerline and distributions of average temperature along the doorway centerline and corner stack were compared with measurements for three different fire sizes, 7.65, 21.25 and 51.71kW. The results showed FDS predicted a very rapid fire growth compared with the experiment for all the three fire sizes, that is an importand shortcoming of FDS in compartment fire simulations. The average temperature distributions, and heights of hot gas layers and neutral planes in steady state were in reasonable agreement with the measurements.