Toluene oxidation was measured over Pt nanoparticles synthesized using a modified polyol reduction method and deposited on ionically conductive yttria-stabilized zirconia (Pt/YSZ) for three different loadings (1.1, 0.8, 0.4 %), and non-ionically conductive gamma-alumina (Pt/gamma-Al2O3) as a comparison (metal loading 0.7 %). It was found that nanoparticles supported on YSZ, tested as a support for the first time for toluene oxidation, have greater catalytic activity compared to a conventional gamma-Al2O3 support in spite of a lower specific area and Pt dispersion. This could be explained by the stronger metal-support interactions between Pt and YSZ due to the ionic conductivity of YSZ and presence of oxygen vacancies.