Abstract: Thirty-seven specimens of human fetal livr cells, obtained during spontaneous bortion and stored in liquid nitrogen for 1 to 793 days, were evaluated for viability using he ranulocyte-macrophage （GM-CFU-C） assay and the dye exclusion test. In the postthawing fetal iver suspension, the rates of nuclear cell recovery and trypan blue exclusion were 97.97±0.68% and 75.68±17.29% respectively, with a mean GM-CFU-C yield of 218.63±139.50/2×10⁵ ucleated cells.Eleven patients with aplastic anemia, acute leukemia, and liver failure have een given infusions of thus cryopreserved fetal liver cells. These patients were benefited rom his highdose cytoreductive therapy with cryopreserved fetal liver cells. Two children with cute leukemia showed sucessful engraftment and the graft was proved by means of genetic arkers s the donor’s karyotypes.The data presented here indicate that human fetal liver cells can be reserved in -196℃ for two years without significant loss of viability, and cryopreserved etal iver cells can be used with success in clinical practice without inducing harmful side ffects.