The　influences　of　temperature,　pressure,　catalyst　content,　H2O2　content　and　mol　ratio　of　propylene　to　H2O2　on　epoxidation　of　propylene　with　H2O2　over　TS-1　in　a　small-scale　three　phase　loop　thermosphonic　reactor　were　investigated.　The　proper　reaction　condition　was　determined　as　follows:　mol　ratio　of　propylene　to　H2O2　was　1.1—1.3,　temperature　was　30—45?℃,　reaction　temperature　rise　was　below　15?℃,　pressure　was　0—0.1?MPa,　catalyst　content　was　3%—6%，and　H2O2　content　was　3%—5%.The　conversion　of　H2O2　is　above　94%,and　selectivity　of　propylene　is　up　to　96%.　At　these　conditions,　the　yield　of　PO　is　higher　than　a　figure　of　about　80%,which　is　achieved　using　conventional　reactor.　This　reactor　can　realize　catalyst　regeneration　continuously.　This　viable　reactor　can　also　be　applied　in　other　oxidation　processes　using　TS-1,　i.e.　hydroxylation　of　phenol,　ammoxidation　of　cyclohexanone.The　results　will　lay　a　foundation　for　the　development　of　the　reactor　in　propylene　epoxidation　process.