Abstract: The effects of different cryopreservation methods of Holstein cow mammary epithelial cells on its viability were studied. Primary bovine mammary epithelial cells were passing five generations and adjusting the cell density to 1×106 cells/mL,and then being cryopreserved by 6 different methods.The viability of cells including mortality,adhering dish rate,apoptosis rate was measured after being recovered.The results showed that the death rate of cell being cryopreserved by treatments 2,3,5 was significantly different from treatment 1（P0.01）.Whereas no significant difference was found among treatments 1,4 and 6（P 0.05）.There was significantly different for death rate of cryopreserved cell between treatment 2 and 6（P0.01）.Adhering rate of cryopreserved cell from treatment 4 was significantly higher than treatment 2,5 and 6（P0.01）.Cell growth state of treatment 1 and 4 were better than others. The results indicated that the treatment 4 was the best cryopreservation method in this study.