A model for liver fibrosis was prepared using CCl4 injected into rats. Human cord blood-derived mononuclear cells (MNCs) were cultured. CD34+ cells were isolated from MNCs. A candidate CD34+ stem cell population were separated from CD34+ cells by adherence to tissue culture plastic. Cells were cultured with and without hepatic differentiation medium. Rats were divided into groups and injected with differentiated and undifferentiated cells through intrahepatic and intravenous routes aiming to evaluate the ability of these cells to reverse hepatic fibrosis. The results of the present study show a significant elevation in serum albumin after administration of stem cells compared to the CCl4 group. IV. Differentiated cells was significantly lower than the other groups that received stem cells. As regards liver enzyme, ALT, there was a significant decrease of its level compared to the CCl4 group. However, it was still significantly higher than control with no significant difference between the groups that received stem cells. Histopathological examination of liver tissue showed that stem cells have a significant antifibrotic effect with no significant difference between the groups that received stem cells. Concerning gene expression, the collagen gene (rat) was highly expressed in the CCl4 group whereas its expression was significantly decreased after administration of stem cells with no significant difference between the groups that received stem cells.The human albumin and matrix metalloproteinase (MMP2) genes were expressed in liver tissues in the groups that received stem cells. Highest expression was in the group that received undifferentiated cells IV.The results of the present work reveal that administration of CD34+ stem cells derived from human cord blood can ameliorate liver fibrosis in rats. The degree of differentiation and route of administration didn’t affect liver functions or the degree of fibrosis.