In this study, the effects of high frequency ultrasound (US) and visible light (VL) on virus inactivation were investigated. The bacteriophages ΦX174 and MS2 were used as model viruses. The experiments were performed at room temperature at three different, relatively high US frequencies (i.e., 582, 862, and 1142 kHz) with and without the use of VL, and different initial virus concentrations. The two bacteriophages were diluted in phosphate-buffered saline solution to a titer of 10(3)-10(4)pfu/mL. The experimental virus inactivation data were satisfactorily represented by a simple first-order kinetic expression.