<正> We present here a comparative study on the transplantation of freshand cryopreserved fetal liver cells（FLC）in mice.The results indicated that the30-day survival rates after transplantation were 38.8%（26/67）for recipients infusedwith fresh fetal liver cells and 54.5%（42/77）for those received cells cryopreservedin liquid nitrogen for 2-103 days.The viability assay showed that the frozen-thawed cells still had an intact viability and repopulating capacity.Ourinvestigations demonstrate that the infusion of fetal liver cells preserved in-196℃ and thawed rapidly could achieve hematopoietic reconstitution in lethallyirradiated mice.