Abstract: <SPAN lang=EN-US>Rare-earth heteropoly salt</SPAN><SPAN style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman"">,</SPAN><SPAN lang=EN-US>Na<SUB>13</SUB>\[Yb(TiW<SUB>11</SUB>O<SUB>39</SUB>)<SUB>2</SUB>\]&#8226;xH<SUB>2</SUB>O</SPAN><SPAN style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman"">,</SPAN><SPAN lang=EN-US>was prepared.The influence of rare-earth heteropoly salt as photocatalyst on photocatalytic degradation of dye wastewater simulated by methyl orange solution was studied.Results showed that the efficiency of degradation was evident.Several important influencing factors of photocatalytic degradation,which included initial pH of solution,catalyst dosage,and initial mass concentration of solution etc.,were discussed.Finally,the kinetics of rare-earth heteropoly salt degrading 10 mg/L methyl orange by using 300 W ultraviolet lamp as photo source was investigated. <BR></SPAN>