Objective To explore the middle-term outcome of autologous bone marrow mononuclear cells transplantation in the treatment of lower l imb ischemia. Methods From March 2003 to June 2005, 65 patients with lower l imb ischemia were treated by autologous bone marrow mononuclear cells transplantation. Of the patients, there were 50 males and 15 females, with a mean age of 66.5 years (range 36-89 years), including 4 cases of simple arteriosclerotic occlusion,5 cases of thromboangiitis obl iterans and 56 cases diabetic lower l imb ischemia. A total of 400 mL bone-marrow blood were extracted from the posterior superior il iac crest. And then the mononuclear cells were isolated from the bone-marrow blood in the laboratory. The amount of transplantation bone marrow mononuclear cells was (0.60-1.80) × 109 (mean 1.05 × 109). Twelve patients received cell transplantation from two to four times and the other patients one time. According to the improvement of cl inical finding, the outcome was evaluated. Results All the patients were followed up for 8-56 months (mean 21.5 months). There were 8 deaths, and the mortal ity was 12.3%; 5 were due to myocardial infarction and heart failure and 3 were due to cerebral infarction. The general effective rate was 70.8% (46/65) and the recurrent rate was 10.7% (7/65). Of them, the response to treatment lasted over 12 months in 42 cases, accounting for 91.3% (42/46); over 24 months in 24 cases, accounting for 52.2% (24/46); and over 37 months in 12 cases, accounting for 26.1% (12/46). The effective rates were 100% in 12 patients who received 2-4 times transplantation and 64.2% in 53 patients who received 1 time transplantation, showing statistically significant difference between them (P lt; 0.001). Conclusion The middle-term outcome of autologous bone marrow mononuclear cells transplantation show that it is a feasible and simple method for treatment of lower l imb ischemia.