The　rose-flower-like　BaSb2O6　(R-BaSb2O6)　and　marigold-flower-like　BaSb2O6　(M-BaSb2O6)　have　been　successfully　prepared　by　a　simple　hydrothermal　method　avoiding　high　temperature,　templates,　catalysts,　surfactants,　or　organic　solvents.　Their　structures　and　morphologies　have　been　investigated　by　X-ray　powder　diffraction,　scanning　electron　microscopy,　transmission　electron　microscopy　and　selected-area　electron　diffraction.　Ba/Sb　molar　ratio　and　pH　values　in　the　precursor　play　significant　roles　in　building　two　kinds　of　flower-like　BaSb2O6.　Time　dependent　experiments　reveal　the　possible　formation　mechanisms　of　the　BaSb2O6　microstructures.　When　used　as　a　photocatalyst,　the　M-BaSb2O6　exhibits　the　best　photocatalytic　activity　among　R-BaSb2O6,　M-BaSb2O6　and　BaSb2O6　synthesized　by　solid　state　reaction.　The　morphology　of　M-BaSb2O6　results　in　the　large　BET　specific　surface　area　and　unique　light　propagation　mode,　which　greatly　improve　the　interaction　among　photons,　organic　compounds　and　photocatalyst,　and　thus　enhance　photocatalytic　activity.　The　photocatalytic　stability　experiments　demonstrate　the　sufficient　stability　of　M-BaSb2O6　during　the　photocatalytic　process.