Marigold-like　ZnIn2S4　microspheres　were　synthesized　by　a　microwave-assisted　hydrothermal　method　with　the　temperature　ranging　from　80　to　195　degrees　C.　X-ray　diffraction,　X-ray　photoelectron　spectroscopy,　nitrogen　sorption　analysis,　UV-visible　spectroscopy,　scanning　electron　microscopy　and　transmission　electron　microscopy　were　used　to　characterize　the　products.　It　was　found　that　the　crystallographic　structure　and　optical　property　of　the　products　synthesized　at　different　temperatures　were　almost　the　same.　The　degradation　of　methyl　orange　(MO)　under　the　visible　light　irradiation　has　been　used　as　a　probe　reaction　to　investigate　the　photocatalytic　activity　of　as-prepared　ZnIn2S4,　which　shows　that　the　ZnIn2S4　sample　synthesized　at　195　degrees　C　shows　the　best　photocatalytic　activity　for　MO　degradation.　In　addition,　the　photocatalytic　activities　of　all　the　samples　prepared　by　the　microwave-assisted　hydrothermal　method　are　better　than　those　prepared　by　a　normal　hydrothermal　method,　which　could　be　attributed　to　the　formation　of　more　defect　sites　during　the　microwave-assisted　hydrothermal　treatment.　(C)　2011　Elsevier　Inc.　All　rights　reserved.