The present investigation reports the novel synthesis of acrylic fibers containing Ag nanoparticles under ultrasound irradiation. The effect of temperature and power of ultrasound irradiation in growth of the Ag nanoparticles were studied. The physicochemical properties of the nanoparticles were determined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results show a decrease in the particles size as the power of ultrasound irradiation decreased. Particle sizes and morphology of nanoparticles depend on temperature. As a result, an increase in temperature led to increase of particle size. The textile containing nanoparticles were tested for their antibacterial efficacy against E. coli and S. aureus and were found to possess significant antibacterial activity.