A rotating gold disk electrode was modified with a ferrocenecarboxamidoyl monolayer, which is ionically bound to a well-ordered zirconium phosphonate film on electrode surface. Voltammetric behaviors on a modified Au disk electrode have been studied in solutions containing electroactive species. This electroactive film with constant thickness of ca. 29 Angstrom simultaneously shows not only an electron-transfer blocking property but also an electron-transfer mediating property. The limiting steady-state current was measured as a function of rotation rate and overpotential for monomer-mediated oxidation of Fe(CN)(6)(4-) and was analyzed to get kinetic parameter values (k(et), K-0, and alpha) by a simulation fitting program. The extracted values of rate constant for the monomer/redox couple electron-exchange reaction and the irreversible charge transport reaction indicate that a relatively facile electron transfer reaction occurs in the high overpotential region even though the zirconium phosphonate film makes the electron propagation rate through the film slower.