Objective To explore vitrified method and cryopreservative solution of mouse oocytes. Method The oocytes of ICR and C 57 BL/6J mice were vitrified with EFS40(high concentration of sodium) and DEFS40(low concentration of sodium),thawed with 0.5mol/L sugar solution.Before fertilization in vitro, zona-pellucieda of C 57 BL/6J mice thawed oocytes were dissected. Results Considering the vitrified effect, DEFS40 is better than EFS40. The oocyte survival rate of ICR mice reaches 75.2% after thawed. The fertilization rate reaches 24.6% and the difference is not remarkable compared to the control.And the oocyte survival rate of C 57 BL/6J mice reaches 87.1% after thawed. The oocyte fertilized rate which zona-pellucieda were dissected reaches 46.0% and the difference is not remarkable compared to the control.Conclusion The vitrified effect of mice oocyte is influenced by the concentration of sodium.The perfect effect could be obtained when the oocytes were vitrified with DEFS40.