Abstract: Objective To investigate the clinical therapeutic effect of umbilical blood stem cell transplantation on patients with decompensated liver cirrhosis. Methods Total of 16 patients with decompensated liver cirrhosis treated with umbilical stem cells were Child-Pugh class B or C. The therapeutic stem cells were collected and isolated from the umbilical blood of fetal delivered by normal or uterine-incision woman. The isolated stem cells were transplanted into the liver via hepatic artery. The manifestation, ascites, biochemical test, prothrombinal function and AFP were observed before and after treatment for 2,4,12 weeks. The volume of liver by MRI were measured and also 12 weeks’follow-up visit were finished. Results After 12 weeks of stem cells treatment, the clinical symptoms improved obviously. The refractory ascites disappeared in 14 cases (87.5%); the edema of lower extremity isappeared in all patients. The albumin level were elevated from 29.8 g/L to 36.2 g/L, the amplification reached 6.4 g/L (P ＜ 0.01), and pre-albumin were elevated from 72.46 mg/L to 107.11 mg/L, the amplification reached 34.65 mg/L (P ＜ 0.01). The prothrombin time activity (PTA) increased from 46.4% to 53.26% (P ＜ 0.01). The serious adverse effects were not observed in all patients. The liver volume detected by MRI enlarged in 11 of 16 patients (69%), the average amplification reached 9.7%. Conclusions Umbilical blood stem cell therapy was effective in the symptoms improvement, ascites clearance, the liver synthetic potency of albumin and pre-albumin and prothrombin function improvement on patients with decompensated liver cirrhosis.