Ribavirin (RBV), a synthesized broad-spectrum antiviral drug, was found to significantly quench the electro-chemiluminescence (ECL) emission of Ru(bpy)(3)(2+) /triethylamine (TEA) system in a pH 11.5 phosphate buffer solution. Based on the UV-visible absorption spectra, cyclic voltammograms and ECL curves study, we reckoned that the ECL quenching may be attributed to the interaction between RBV and the electrogenerated TEA free radical-a strongly reducing free radical which can effectively enhance the ECL of Ru(bpy)(3)(2+). Based on the quenching effect of RBV on Ru(bpy)(3)(2+) /TEA, a simple, rapid and sensitive method for the analysis of RBV was proposed. Under the optimal conditions, the logarithm of RBV concentration versus the quenched ECL intensity was linear over the ranges of 2 x 10(-7) -5 x 10(-5) M, with a detection limit of 8.5 x 10(-8) M (S/N = 3) in a pH = 11.5 0.05 M phosphate buffer solution containing 5.0 x 10(-6) M Ru(bpy)(3)(2+) and 1.0 x 10(-6) M TEA. To verify its practicability, the proposed method was employed to the determination of RBV in tablets and the recoveries were ranged from 93%-102%.