Abstract:Abstract：The onion polysaccharides were extracted by compound enzyme of cellulose，papain and neutralprotease from onion. The effects of compound enzyme concentration，extraction time，extraction temperature，pHand liquid-solid ratio were investigated. The extraction technology was optimized by orthogonal experimentationon the basis of a series of single -factor experiments. The optimal conditions of extraction were obtained asfollows：compound enzyme dosage was 0.3 %，enzymolysis temperature was 50 ℃，enzymolysis time was 75min，buffer solution pH was 6.0，and solid-liquid ratio was 1 ∶ 35（g/mL），the polysaccharides yield reached18.75 % and the purity reached 62.00 %. The yield and purity of onion polysaccharide was improved bycompound enzyme.