Zirconium tungsten oxyfluoride,ZrWO4F2,was firstly synthesized with the pr ecursor route.The composition of the compound was determined by combi ning the results of ICP and XPS.The in dexed powder X-ray diffraction pattern of this compound indicates t hat it is a pure phase,orthorhombic c rystal system,space group D 22 =P2 1 22and a=15.32（2）*!,b=13.877（7）*!,c=8.42（2）*!.Combining the results of the DTA-T GA curves from room temperature to 700℃and XRD patterns in different temperatures the mechanism was revealed during the solid precursor（1）been heated to 700℃.The zirconium tu ngsten oxyfluoride was considered t o be a metastable com-pound.The ascertaining of annealin g time and temperature is the key of handling.
