A　polyphenol　oxidase　(PPO)　from　lotus　seed　was　purified　by　the　procedures　including　ammonium　sulphate　precipitation　and　affinity　chromatography.　The　apparent　molecular　mass　was　38.6　kDa　by　SDS-PAGE.　Kinetic　studies　showed　that　the　Km　and　Vmax　values　for　catechol　were　6.04 mm　and　416.67 U,　respectively.　The　PPO　performed　optimal　activity　in　20 °C　and　pH　7.0.　The　enzymatic　activity　could　be　mainly　maintained　up　to　50 °C　and　pH　4.0-7.0.　The　activity　could　be　inhibited　by　various　inhibitors　including　thiourea,　urea,　sodium　hydrogen　sulphite,　EDTA·2Na,　SDS,　citric　acid,　guanidine　hydrochloride,　ascorbic　acid,　sodium　sulphite　and　sodium　thiosulphate.　The　metal　ions　Ba2+,　Mg2+,　Ca2+,　Mn2+,　Co2+　and　Zn2+　could　inhibit　the　activity　of　PPO,　while　Cu2+　performed　obvious　enhancement.　The　enzymatic　properties　of　PPO　could　probably　provide　practical　application　in　inhibiting　the　PPO　activity　and　preventing　enzymatic　browning　in　the　process　of　picking,　transportation,　processing　and　storage　of　fresh　lotus　seeds.　©　2015　Institute　of　Food　Science　and　Technology.