Abstract: The steady state multiplicity features of carbon monoxide oxidation reaction on platinum catalyst have been experimentally studied. The experimental results were treated with the help of singularity theory and catastrophe theory, and the number of steady states that were likely to exist was found. In addition, the types of the bifurcation diagram, which describes the relation of state variable to the operation parameters for the reaction system, can be predicted in the operation parameter region having different number of steady states. Finally, it has been realized that it is possible to identify the reaction kinetic model by using the steady state multiplicity features of the system, and a satisfactory result can be obtained.