Poly(vinyl alcohol) (PVA)/silver (Ag) nanocomposite fibers were prepared by electrospinning in a one-pot process. The fibers were characterized by SEM, EDS, XRD and UV-Vis diffuse reflectance spectroscopy. The antibacterial activities of the nanofibers were investigated. The SEM images showed that the diameter of electrospun fibers with 10 wt% PVA attained average values around 90 nm. The X-ray diffraction patterns, the EDS spectrum and the UV-Vis diffuse reflectance spectra confirmed the presence of the silver nanoparticles on the fibers. These nanofibers showed good values of antibacterial activities against Staphylococcus aureus (87.8%) and Escherichia coli (85.0%).