Hexagonal　YBO3　photocatalysts　were　successfully　synthesized　by　hydrothermal　method.　The　samples　were　characterized　by　XRD,　SEM,　TEM,　XPS,　UV-vis,　photocatalytic　performance,　photocurrent　and　electrochemical　impedance　analysis.　The　results　show　that　the　pH　value　has　a　large　effect　on　the　formation　of　the　microspheres.　The　excellent　photocatalytic　performance　for　RhB　degradation　depends　on　the　exposed　{1　0　(1)　over　bar0}　facets　in　which　the　fitting　concentration　of　oxygen　vacancy　can　prevent　the　recombination　of　the　photogenerated　carriers.　Meantime,　the　{1　0　(1)　over　bar0}　faceted　YBO3　microspheres　enhance　the　absorption　of　irradiation　light　and　present　highest　specific　surface　area　which　can　also　accelerate　photocatalytic　activity.