During recent 3 years, the authors had treated surgically 31 patients who have had old nerve injuries. 19 patients(21 nerves) of them could be followed for more than 1 year after operation. Of these patients, children were 5 and adults were 14. The elapsed time from the injury were from 3 weeks to 20 months(18 cases under 6months and 3 cases above 6 months). The methods of operation were epineural suture(4 cases), grouped interfascicular suture(8 cases), neurolysis(8cases) and nerve graft(1 case). There were satisfactory or good results in 9 nerves of the 21 old nerve injuries. In 4 of 5 children and 5 of 16 adults, good results were obtained. There were 2, 6 satisfactory or good results in 4 epineural sutures and 8 grouped interfascicular sutures and all poor results in 8 neurolyses. One case treated with nerve graft with sural nerve was showed good result. 9 cases of 18 old injuried nerves under 6 months from injury were good results. All 3 cases over 6 months from injury were poor results.