A glassy carbon electrode modified with poly lamotrigine film（PLTG/GCE） was fabricated. The poly lamotrigine film was deposited at the glassy carbon electrode by cyclic voltammetry in H2SO4 solution. The electrode was characterized by alternating current（AC） impedance. NO-2 was determined by the differential pulse voltammetry（DPV） using the electrode in KH2PO4 and Na2HPO4 buffer solution. The modified electrode exhibited good electrocatalytic response to the oxidation of nitrite．A good linear relationship was obtained between the anodic peak currents and NO-2 concentrations in the range of 96×10-6-11×10-3 mol?L-1 （correlation coefficient r=0998 8） with a detection limit of 32×10-6 mol?L-1. The proposed method was applied for the determination of NO-2 in real water samples with satisfactory results.