Some microorganisms became less sensitive to several ordinary used antibiotics, causing the outbreak of infectious diseases. Therefore, the present study is carried out to investigate the antibacterial properties of silver and zinc oxide nanoparticles. Their physicochemical properties as well as the combined effects of antibiotics previously impregnated with the metal and metal oxide nanoparticles. Silver nanoparticles (AgNPs) were obtained using the chemical reduction method, while zinc oxide nanoparticles (ZnONPs) were synthesized using the precipitation method followed by calcination process. The formed nanoparticles (Nps) were characterized using UV-Visible spectroscopy, Fourier Transforms Infrared Spectroscopy (FT-IR), X-ray diffraction analysis (XRD) and Transmission Electron Microscopy (TEM). The antibacterial effect of AgNPs and ZnONPs was tested against four different genera: Staphylococcus aureus (Gram positive), Shigella boydii (Gram negative), Klebsiella pneumoniae (Gram negative) and Escherichia coli (Gram negative) and showed strong effect against all. Also, the synthesized nanoparticles were evaluated for their role in increasing the antibacterial activity of ten tested antibiotics which cover most antibiotics groups according to their mechanism of action. Enhancement in the antibiotic activities was recognized via increasing inhibition zone diameters (mm).