Plasma technology offers an appealing approach for the surface modification of materials such as textiles. In this study, an atmospheric pressure plasma jet system was used to successfully deposit silver nanoparticles on polyester textile substrates to impart antibacterial properties. The plasma was generated by applying a constant potential of 15 kV to silver electrodes while argon and oxygen gases were allowed to flow at 15 and 5 LPM, respectively. The optical emission spectra of the generated plasma revealed the presence of argon, oxygen, and silver species. The combination of operating parameters employed in the study led to the successful deposition and adhesion of silver nanoparticles without changing the bulk properties of the material. The deposited silver nanoparticles were verified using a scanning electron microscope analysis which showed an expected increase in particle density at longer plasma exposure time. Qualitative and quantitative antibacterial assays proved the efficiency of the plasma-treated textile samples in inhibiting the growth of the Gram- negative Escherichia coli and the Gram-positive Staphylococcus aureus bacteria. The antibacterial efficiency of the treated samples proportionally increased with longer plasma treatment time. The approach used in this study successfully produced surface-immobilized silver nanoparticles polyester textile with potential application as antibacterial fabrics.