Nickel hexacyanoferrate films have been deposited on the surface of a microband gold electrode by cyclic voltammetry.Cyclic voltammograms of the resulting nickel hexacyanoferrate films indicate the presence of a couple of redox peaks whichcorrespond to the hexacyanoferrate(II/III) redox couple. The nickel hexacyanoferrate modified microband gold electrodeshows an excellent electrocatalytic activity for oxidation of reduced nieotinamide adenine dinueleotide (NADH) inphosphate buffer solution (pH 7.0), with an overpotential ca. 340mV lower than that of the bare electrode. The steady-statecurrent increases linearly with NADH concentration in the range of 0.5-8.0 mmolx. The catalytic rate constant of themodified electrode for the oxidation of NADH is determined using a rotating disk electrode. The further experimental resultsshow that the rate constant decreases with increasing NADH concentration. The mechanism of the oxidation of NADHcatalyzed by the nickel hexacyanoferrate modified gold electrode is discussed.