We investigated the antiviral activity of TiO2-coated cordierite foam used in air cleaners, as well as the evaluation methodology. Furthermore, we developed Cu2+/TiO2-coated cordierite foam and investigated the reduction in viral infection ratio. The method for evaluation of antibacterial activity of TiO2-coated cordierite foam could also be applied to evaluation of antiviral activity. We showed that Cu2+/TiO2-coated cordierite foam reduced the viral infection ratio to a greater extent than TiO2-coated cordierite foam. Our findings suggest that the infection risk by polluted air could be decreased using Cu2+/TiO2-coated cordierite foam in air cleaners. (C) 2012 Elsevier B.V. All rights reserved.