Porous　ZnO　microspheres　with　an　average　size　of　around　500　nm　had　been　synthesized　by　thermal　treatment　of　ZnS　microspheres　in　an　air　atmosphere.　The　ZnS　spheres　had　been　synthesized　at　a　low　temperature　of　100　degrees　C　by　using　L-cysteine　(an　ordinary　amino　acid)　as　a　sulfur　source　with　the　assist　of　gelatin.　By　combining　the　results　of　X-ray　diffraction　(XRD),　transmission　electron　microscope　(TEM),　field-emission　scanning　electron　microscopy　(FE-SEM),　and　Fourier　transformation　infrared　spectra　(MR),　a　structural　and　morphological　characterization　of　the　products　was　performed.　The　photocatalytic　activity　of　ZnS　microspheres　and　porous　ZnO　microspheres　have　been　tested　by　degradation　of　Rhodamine-B　(RB)　under　UV　light,　indicating　that　the　porous　ZnO　microspheres　showed　enhanced　photocatalytic　performance　compared　to　ZnS　microspheres　and　commercial　Degussa　P25　TiO2.　(C)　2009　Elsevier　B.V.　All　rights　reserved.