In　order　to　investigate　the　influence　of　particle　morphology　on　the　catalytic　activity　of　supported　Pt　model　catalyst,　platinum　nanoparticles　(NPs)　with　different　morphologies　were　synthesized　by　a　chemical　method　and　loaded　onto　SiO2　to　give　well-defined　supported　catalysts.　CO　oxidation　was　used　as　the　probe　to　investigate　the　catalytic　activities　of　these　Pt/SiO2　model　catalysts.　X-ray　fluorescence,　X-ray　photoelectron　spectroscopy,　diffuse　reflectance　Fourier　transform　infrared　spectroscopy,　and　transmission　electron　microscopy　characterization　demonstrated　that　the　different　activities　of　these　Pt/SiO2　catalysts　were　due　to　different　crystal　surfaces,　which　strongly　influenced　the　adsorption　and　oxidation　of　CO　on　the　Pt　NPs.