Abstract: A numerical simulation was conducted on the operation performance of a reverse flow catalytic reactor with inlet concentration of reactants periodically fluctuated. Taking methane and propane as the model reactants, the effects of following factors on the operation performance of the reactor were studied, such as the fluctuation cycle of reactant concentration, the switching period of flow direction, the superficial velocity and the addition of supplimental fuel, etc. Results show that when the fluctuation cycle of reactant concentration equals to the switching period of flow direction, resonance response would occur in the reactor, indicating in the increase of maximum temperature, decrease of average temperature, and increase of bed temperature fluctuating amplitude, resulting in reduced thermal stability of the reactor. Above resonance phenomenon and temperature oscillation could be inhibited by increasing the superficial velocity or adding supplemental fuel to compensate the instantaneous fluctuation of inlet concentration of relevant reactants.