Silver nanoparticles (Ag NPs) have been deposited on the surface of cotton fabrics by a facile two-step method involving liquid precipitation and dielectric barrier discharge (DBD) cold plasma reduction. X-ray diffraction, X-ray photoelectron spectroscopy and high-resolution TEM show that Ag exists only in the metallic state form on the surface of the cotton fibers after DBD plasma treatment, demonstrating that DBD plasma is a promising technique for metallic oxide in situ reduction. The Ag NPs-modified cotton fabrics exhibit the significant antibacterial property against both Escherichia coli and Staphylococcus aureus, which have potential applications in the healthcare and medicine fields.