Objective To compare the survival and developmental potential of mouse morula, early blastocysts and blastocysts cryopreserved by vitrification. Methods One hundred and forty-two mouse morula, 135 early blastocysts and 148 blastocysts were cryopreserved by 6 mol/L ethylene glycol and 1 mol/L sucrose vitrification solutions. The survival rates and blastocysts hatching rates after thawing were observed. Results The survival rates of morula, early blastocysts and blastocysts groups were 88. 0% ,73. 3% ,and 60. 1% respectively. The blastocyst hatching rates were 73. 9% , 61. 5% ,and 49. 3% respectively. Both the survival rates and blastocyst hatching rates in morula group were higher than those in early blastocysts group (P