||18-50nm sized copper oxide nanoparticle has been synthesized by an ecofriendly method where seed electrolyte of Vigna radiata act as a phytoreducer to reduce three different copper salts separately [copper (nitrate, sulphate, chloride)]. Fastest reaction followed by smallest nanoparticle was obtained when electrolyte reacted with copper nitrate. Morphology and charge distribution of nanoparticle was confirmed by characterization and to indentify different phytochemicals which are present in electrolyte, different phytochemical assays were performed by standard techniques. This experiment showed that phenols and flavonoids present in the electrolyte are the main phytoreducer to generate negatively charged copper oxide nanoparticle. Also nanoparticles showed antibacterial activity against S.aureus. So the experiment specified that nanoparticle could be generated by a low cost, nontoxic, ecofriendly method which could be further applied in different aspects of pharma industry to ameliorate living standard and health care.