Biological synthesis of nanomaterials offers numerous advantages over chemical synthesis. This study was aimed at the synthesis of biosynthesized copper nanoparticles using Staphylococcus aureus. Biosynthesis of CuSO4 nanoparticles using Staphylococcus aureus isolated from poultry droppings was carried out. Effect of CuSO4 concentration and cell free supernatant on CuNP production was determined. Antimicrobial, and synergistic studies of conventional antibiotics, and CuSO4 mediated samples were carried out also. The CuSO4 nanoparticles was characterized using Energy dispersive X-ray fluorescence. Staphylococcus aureus mediated CuNPs was assessed for antimicrobial properties using some selected bacterial cultures. CuSO4 nanoparticles was produced at varying levels of copper concentration with absorbance highest at 400nm at 750ppm. Inhibition of Streptococcus cohni, Enterococcus rafinose, Serratia marcescens and Salmonella enteritidis was achieved at the tested strengths (318.4ppm, 750ppm, 1000ppm) of CuNPs produced by the Staphylococcus aureus. Significant increase in the activities of tetracycline, gentamycin, vancomycin ranged between 1.9-100% as recorded in this study. Energy dispersive X-ray fluorescence showed Cu as the predominant element. Staphylococcus aureus mediated CuNP showed significant antimicrobial activities.