Development of green technology is generating interest of researchers towards ecofriendly and low-cost methods for biosynthesisof nanoparticles (NPs). In this study, copper oxide (CuO) NPs were synthesized using a copper nitrate trihydrate precursorand Ficuscaricaleaves extract as a reducing and capping agent biosynthesized CuO NPs were characterizedusing an X-ray diffractometer (XRD), scanning electron microscopy energy dispersive X-ray spectroscopy (SEM-EDS),transmission electron microscope (TEM), Ultraviolet visible spectroscopy (UV-Vis), and Fourier transform infrared (FTIR)spectroscopy.antibacterial and antibiofilm activity of Cuo NPs were evaluated by agar well diffusion and micro titer plate method respectively Moreover, the antimicrobial activities of different concentrations of CuO NPs synthesized using Ficuscaricaextract were also tested. Accordingly, the outstanding of antibacterial activity of cuo np was the powerful effect with greater inhibitor zone reach to 35 mm where consider a largest one than other green metal oxide nanoparticles. The result revealed a significant difference between the antibacterial effect of green CuO NPs on human and animal E.coli p value=??. CuONPs demonstrated significant antibacterial activity. Hence, they may be used as an antibacterial agent and could be used as an effective alternative to traditional antibiotics.