Abstract A novel electrochemical method for the synthesis of PbS nanoparticles in aqueous phase was developed for the first time. With lead as the sacrificial anode and poly(N-vinylalcohol) as the stabilizer, PbS nanoparticles were synthesized very conveniently by means of a cyclic voltammetric process at room temperature in a sodium sulfide aqueous solution. This method is based on the fast cycling of the potential applied on the lead electrode between two values. Pb is oxidized to Pb2+ by cycling within a potential range of −0.1 to 1.5 V. The produced Pb2+ reacts with S2− to produce PbS. In this method, O2 bubbles evolved at the lead electrode surface when the potential was scanned to the vicinity of the most positive potential. It was found out that the evolution of O2 could effectively prevent the deposition of PbS film on the electrode surface. XRD and chemical analysis indicate that the product is pure cubic phase PbS. The size and morphology of the particles are studied by TEM.