Mathematical modeling of three-way catalytic converter (3WCC) operation is increasingly employed in automotive catalyst and converter systems optimization. Oxygen storage is known to strongly affect catalytic converter operation under real world transient operating conditions. This paper presents a modeling approach embodying a comprehensive oxygen storage and release submodel into an existing 3WCC quasi-steady model. The dynamic model developed according to this approach is validated against previously published experimental data. The model sensitivity to each of the oxygen storage parameters is examined. The results of this investigation encourage further application of mathematical modeling in areas such as air-to-fuel (A/F) ratio control strategy optimization, which lie beyond the scope of traditional kinetic 3WCC models.