Abstract: Objectctive To explore the protective effect of the recombinant MnSOD or CuZnSOD on the cryopreservation of wild mice sperm. Methods The R18S3 added with different concentrations of recombinant MnSOD or CuZnSOD was used as cryoprotectant to select two of the best concentra-tion of SOD through comparison of the motility，membrane integrity, DNA damage of frozen-thawed ICR mice sperm in each group. Results The motility and membrane integrity of frozen-thawed wild mice sperm increased significantly (P<0.05) adding with 100U CuZnSOD and 200U MnSOD in R18S3 compared to the control group. While there were no difference in the group of R18S3 with 100 U CuZnSOD adding，only in the group of R18S3 adding with 200U MnSOD the fertility rate of frozen-thawed sperm significantly increased compared with the control group (P<0.05). Conclusion The cryoprotectant adding with 200 U recombinant MnSOD has a protective effect on the cryopreservation of wild mice sperm.

Key words: SOD, Mus musculus;Sperm cryopreservation