UV disinfection of drinking water is becoming more common as water utilities attempt to control the formation of disinfection byproducts. While most organisms are readily inactivated by UV, certain viruses require a large fluence for adequate disinfection. In this study, photocatalytic silver doped titanium dioxide nanoparticles were investigated for their capability to enhance the UV disinfection of Bacteriophage MS2. The inactivation kinetics were compared to the base TiO2 material and silver nanoparticles. Inactivation of MS2 was enhanced by doping TiO2 with 8 and 10 wt. % silver, while no enhancement was observed with 4 and 6 wt. % silver. In order to determine the inactivation mechanism, alcohol scavengers were employed to eliminate the effects of hydroxyl free radical. When nAg/TiO2 was used as the catalyst, the alcohols significantly decreased the inactivation rate, but did not completely eliminate the virucidal activity. When P25 TiO 2 was used, no virus inactivation was observed.