Abstract: In this paper,the suitable enzymatic extraction method and the antioxidant activity of Dendrobium officinale polysaccharides(DOP)were studied. The effects of enzymatic ratio,enzyme concentration,temperature,extraction time,solid-liquid ratio and pH on yield of polysaccharides were investigated,on the basis of single-factor experiments and orthogonal test for enzymatic action. The optimized extraction conditions were:Dispase and Cellulase ratio of 2:1,enzyme concentration of 10%,solid-liquid ratio of 1:120,extraction temperature of 55℃,pH6.0,extraction time of 3 h,the yield of polysaccharides were 43.85%±1.8%,antioxidation results showed that the DOP extracted by enzymatic method had an obvious antioxidant activity,the IC₅₀ values of DPPH and ABTS free radical scavenging abilities were 1.331,0.467 mg/mL,Dendrobium officinale polysaccharides had good antioxidant activity.