The unused polysaccharide components in Shenmai injection were extracted by water extraction and alcohol precipitation method,and the auxiliary materials of Shenmai polysaccharide oral liquid were screened.Finally,Shenmai polysaccharide oral liquid was obtained.And three different concentrations of polysaccharide oral liquid were given to mice to explore the anti-fatigue activity.The results showed that 0.1% methyl p-hydroxybenzoate,0.2% CMC-Na and 2% honey were the auxiliary materials of Shenmai polysaccharide oral liquid.Moreover,animal experiments showed that the oral liquid could increase the swimming time,the contents of muscle glycogen,lactate dehydrogenase and phosphokinase in mice,decreased the metabolism accumulation of lactate and urea nitrogen.These results showed that Shenmai polysaccharide oral liquid had anti fatigue effect.