A　novel　Ultrasonic　Assisted　Membrane　Reduction　(UAMR)-hydrothermal　method　was　used　to　prepare　flower-like　Pt/CeO2　catalysts.　The　texture,　physical/chemical　properties,　and　reducibility　of　the　flower-like　Pt/CeO2　catalysts　were　characterized　by　X-Ray　Diffraction　(XRD),　Scanning　Electron　Microscope　(SEM),　Transmission　Electron　Microscope　(TEM),　N-2　adsorption,　and　hydrogen　temperature　programmed　reduction　(H-2-TPR)　techniques.　The　catalytic　performance　of　the　catalysts　for　treating　automobile　emission　was　studied　relative　to　samples　prepared　by　the　conventional　wetness　impregnation　method.　The　Pt/CeO2　catalysts　fabricated　by　this　novel　method　showed　high　specific　surface　area　and　metal　dispersion,　excellent　three-way　catalytic　activity,　and　good　thermal　stability.　The　strong　interaction　between　the　Pt　nanoparticles　and　CeO2　improved　the　thermal　stability.　The　Ce4+　ions　were　incorporated　into　the　surfactant　chains　and　the　Pt　nanoparticles　were　stabilized　through　an　exchange　reaction　of　the　surface　hydroxyl　groups.　The　SEM　results　demonstrated　that　the　Pt/CeO2　catalysts　had　a　typical　three-dimensional　(3D)　hierarchical　porous　structure,　which　was　favorable　for　surface　reaction　and　enhanced　the　exposure　degree　of　the　Pt　nanoparticles.　In　brief,　the　flower-like　Pt/CeO2　catalysts　prepared　by　UAMR-hydrothermal　method　exhibited　a　higher　Pt　metal　dispersion,　smaller　particle　size,　better　three-way　catalytic　activity,　and　improved　thermal　stability　versus　conventional　materials.