The commonly used cryoprotectants have poor effect on sperm freezing and thawing of asthenospermia.In this experiment,the Epimedium polysaccharide (EPS) was added to the human sperm cryoprotection solution to study its effect on the sperm motility and sperm function influences.15 cases of asthenospermia semen were selected.The liquefied semen samples were mixed with glycerin yolk citrate (GEYC) cryoprotectant or EPS cryoprotectant respectively.The sperm viability,survival rate,morphology,MDA,ROS,DFI and AR were measured,and the changes of sperm microstructure were observed by transmission electron microscopy.After adding EPS,the level of MDA and ROS in spermatozoa decreased significantly,and the antioxidant activity of frozen group containing 3 mg/mL EPS was better than that of other groups(P＜0.05);The survival rate and normal morphology rate of sperm head in the frozen group with EPS were significantly higher than those in the control group,but there was no significant difference in the PR of sperm forward movement between the two groups.In addition,the DFI and AR of sperm in the frozen group added EPS decreased significantly,and the ultrastructure of sperm head showed that the integrity of plasma membrane and acrosome membrane of sperm in the EPS group was significantly better than that in the control group.The results showed that adding EPS to semen cryoprotectant could reduce the level of sperm ROS,protect the structure and function of sperm acrosome,and improve the acrosome function and the integrity of sperm nucleus after thawing.