Ag nanoparticle deposition on the surface of spherical SiO2 nanoparticles was studied to achieve hybrid structure of Ag-SiO2 nanocomposite. SiO2 nanoparticles were served as seeds for continuous Ag metal deposition. The ratio of elements and morphology was studied with scanning electron microscope energy dispersive X-ray and transmission electron microscope. The antibacterial properties of Ag-SiO2 nanocomposite were examined. The homogeneously formed Ag nanoparticles on the surface of SiO2 nanoparticles without aggregation of Ag nanoparticles showed excellent antibacterial abilities.