Noble　metal/semiconductor　nanocomposites　play　an　important　role　in　high　efficient　photocatalysis.　Herein,　we　demonstrate　a　facile　strategy　for　fabrication　of　hollow　Pt-ZnO　nanocomposite　microspheres　with　hierarchical　structure　under　mild　solvothermal　conditions　using　Zn　(CH3COO)　2·2H2O　and　HPtCl4　as　the　precursors,　and　polyethylene　glycol-6000　(PEG-6000)　and　ethylene　glycol　as　the　reducing　agent　and　solvent,　respectively.　The　as-synthesized　ZnO　and　Pt-ZnO　composite　nanocrystals　were　well　characterized　by　powder　X-ray　diffraction　(XRD),　nitrogen-physical　adsorption,　scanning　electron　microscopy　(SEM),　energy　dispersive　X-ray　(EDX),　transmission　electron　microscopy　(TEM),　X-ray　photoelectron　spectroscopy　(XPS),　UV-vis　diffuse　reflectance　spectra　(DRS),　and　photoluminescence　(PL)　emission　spectroscopy.　It　was　found　that　Pt　content　greatly　influences　the　morphology　of　Pt-ZnO　composite　nanocrystals.　Suitable　concentration　of　HPtCl4　in　the　reaction　solution　system　can　produce　well　hierarchically　hollow　Pt-ZnO　nanocomposite　microspheres,　which　are　composed　of　an　assembly　of　fine　Pt-ZnO　nanocrystals.　Photocatalytic　tests　of　the　Pt-ZnO　microspheres　for　the　degradation　of　the　dye　acid　orange　II　revealed　extremely　high　photocatalytic　activity　and　stability　compared　with　those　of　pure　ZnO　and　corresponding　Pt　deposited　ZnO.　The　remarkable　photocatalytic　performance　of　hollow　Pt-ZnO　microspheres　mainly　originated　from　their　unique　nanostructures　and　the　low　recombination　rate　of　the　e-/h+　pairs　by　the　platinum　nanoparticles　embedded　in　ZnO　nanocrystals.　©　2013　The　Royal　Society　of　Chemistry.