A polymerized film of eriochrome black T (EBT) was prepared on the surface of pencil graphite electrode in alkaline solution by cyclic voltammetry. The redox response of the poly (EBT) film at the electrode appeared in a couple of redox peak in 0.1 M sodium hydroxide. The poly (EBT) film-coated electrode exhibited excellent electrocatalytic activity towards the oxidation of rabeprazole sodium (RAB sodium) and domperidone (DOM) in Britton-Robinson buffer (pH 4.0). The polymer film modified electrode conspicuously enhanced the redox currents of the cited mixture and could sensitively and separately determine them. Both cyclic voltammetry (CV) and square wave adsorptive stripping voltammetric (SWAdSV) methods were utilized to determine this mixture. The linearity of CV ranged from 4.1- 120 mM and 5.2-90 mM for RAB sodium and DOM, respectively while SWAdSV was 7.5-803107M and 5– 703107M for RAB sodium and DOM, respectively. With good selectivity and sensitivity, the present method provides a simple method for selective detection of RAB sodium and DOM binarybinary mixture in synthetic mixtures and biological fluids.