This paper reports the electrochemical properties of sulpiride at a mercury electrode, especially its adsorptive characteristic. Sulpiride dissolved in a supporting electrolyte of a McIlvaine buffer at pH 6.8 represents a sensitive and well defined reduction wave by linear sweep stripping voltammetry. This method is based on the pre-concentration and the reduction of sulpiride at a hung mercury drop electrode. The reduction peak potential is -1.72 V(vs. Ag-AgCl) and the peak current is proportional to the concentration of sulpiride in the range of 0.1-0.6 μg/mL. The detection limit is 0.025 μg/mL obtained under the experimental conditions selected in this work. The electrochemical properties of this system were investigated, and the proposed method was applied to the determination of sulpiride in pharmaceutical tablets with satisfactory results. It was compared well with the UV spectrophotometric method, showing a superior sensitivity.