Quantum chemical calculations based on density functional theory method were performed on two pyrimidine derivatives which may be used as corrosion inhibitors for austenitic stainless steel. The quantum chemical properties of the two pyrimidine derivatives that are most relevant to their potential action as corrosion inhibitors have been calculated. To explain the inhibition performance of the pyrimidine derivatives, their local reactivities were analyzed through Fukui functions. The binding energies of the inhibitors with the surface of austenitic stainless steels were studied. A model has been suggested to calculate the approximate inhibition efficiencies of the pyrimidine derivatives. All calculations were carried out in both gas and liquid phases.