The　oxidative　degradation　of　chlorinated　ethylenes　with　a　metal-oxo　reagent,　potassium　ferrate　(K2FeO4)　is　investigated　in　this　paper.　The　encapsulated　K2FeO4　was　prepared　by　the　molten　suspension　and　cooling　method,　with　paraffin　wax　and　K2FeO4　solid　as　encapsulated　wall　and　encapsulated　core,　respectively.　The　effects　of　three　main　factors,　stirring　time,　ultrasonic　time　and　temperature　of　water　bath,　on　the　preparation　of　encapsulated　ferrate　were　studied.　The　spectra　of　IR　and　XRD　showed　that　paraffin　wax　would　not　react　with　K2FeO4　and　active　components　of　K2FeO4　remain　unchangeable　during　the　encapsulation　process.　As　a　water　treatment　reagent,　the　encapsulated　ferrate　could　be　stable　enough　to　meet　the　necessity　of　groundwater　temperature　scale,　which　indicted　from　DSC　data.　Experiments　also　showed　that　the　release　kinetics　of　K2FeO4　from　the　encapsulated　particles　was　in　good　agreement　with　Q=ktn　model.　A　detail　research　showed　that　TCE　degradation　could　be　more　effective　in　acidic　medium　as　above　90%　after　reaction　time　60　mins　under　pH　=　4.0-6.0　than　that　in　basic　as　only　80%　after　150　mins　at　pH　=　10.