Orthogonal　design　was　employed　to　study　the　effect　of　extraction　time,　temperature　and　liquid-to-solid　ratio　on　the　production　of　antioxidant　polysaccharides　from　leaves　of　Gynura　bicolor　(PLG).　Analysis　of　variance　was　performed　on　the　data　obtained.　The　most　relevant　variable　was　extraction　time.　A　liquid-solid　ratio　of　30:1　(v/w),　a　temperature　of　80　degrees　C　and　an　extraction　time　of　3　h　were　found　to　be　optimal　for　PLG.　The　optimal　extraction　yield　of　4.9%　was　obtained　through　additional　verification　test.　Hydroxyl　radical-scavenging　activity,　reducing　power　and　ferrous　ion　chelating　ability　of　PLG　were　determined.　PLG　possess　concentration-dependent　antioxidant　potency　and　IC50　of　PLG　was　4.67,　0.24　and　4.31　mg/mL　for　hydroxyl　radical-scavenging　and　ferric　ion　chelating　abilities　as　well　as　reducing　power,　respectively.　The　results　suggest　that　G.　bicolor　polysaccharides　could　be　potential　source　of　natural　antioxidant　and　be　contributor　to　the　health　benefits　of　G.　bicolor.