The electrochemical polymerization of amino-derivatives of naphthalene has been studied on the platinum wire electrodes. The effects of acidity of the modifying media and the potential scan rate on the cyclic voltammograms are verified. As potentiometric pH sensors, the electrodes prepared from 1-naphthylamine and 2,3-diaminonaphthalene showed performance characteristics superior to some other electrodes tested. The electrode modified with 1-naphthylamine in the optimum medium showed a nearly Nernstian response of 4.20–13.70 pH and a slope of -54.8 mV/pH, while the linear range of the electrode prepared by 2,3-diaminonaphthalene was 4.00–13.60 pH, with a slope of -52.4mV