Objective To assess the effect of mitochondria from cumulus granular cells transplanted into early embryos of aging mice.Metheds Kunming mice were used as experiment animal model,and the cumulus granular cells,oocytes,zygotes were used as experimental material.Mitochondria were taken from cumulus granular cells,purified and injected into oocytes and zygotes of ageing mice.Results The blastulation rate of ICSI group and ICSI MIT group were 24.98% and 32.54%,respectively,(P<0.05).The cleavage rate and blastulation rate in the sham injection group were 39.33% and 19.67%,those of MIT group were 67.90% and 51.54%,respectively.There was a significant difference between the sham injection and MIT groups(P<0.05). Conclusion Mithochondria transplantation can improve the development potential of early embryos of ageing mouse.