When explored to UV light nanometer titanium dioxide (TiO2) exhibits a strong bactericidal activity. In this study, nylon fabric was treated by nanometer titanium dioxide particles, which can be photocatalyzed by UV light. We tested the effect of antibacterial and physical properties of treated nylon fabric. The result of this study shows that photocatalysis treated nylon fabric damage both Gram(-) bacteria and Gram(-) bacteria cells. The reduction rate of bacteria is up to treating concentration and UV irradiation time. According to the Titanium dioxide doses, strength of treated Nylon fabrics decreased, and softness increased.