In this study, we loaded human umbilical cord mesenchymal stem cells onto human amniotic membrane with epithelial cells to prepare nerve conduits, i.e., a relatively closed nerve regeneration chamber. After neurolysis, the injured radial nerve was enwrapped with the prepared nerve conduit, which was fixed to the epineurium by sutures, with the cellon the inner surface of the conduit. Simultaneously, a 1.0 mL aliquot of human umbilical cord mesenchymal stem cellsuspension was injected into the distal and proximal ends of the injured radial nerve with 1.0 cm intervals. A total of 1.75 × 107 cells were seeded on the amniotic membrane. In the control group, patients received only neurolysis. At 12 weeks after celltransplantation, more than 80%of patients exhibited obvious improvements in muscular strength, and touch and pain sensations. In contrast, these improve-ments were observed only in 55-65% of control patients. At 8 and 12 weeks, muscular electro-physiological function in the region dominated by the injured radial nerve was significantly better in the transplantation group than the control group. After celltransplantation, no immunological rejec-tions were observed. These findings suggest that human umbilical cord mesenchymal stem cel-loaded amniotic membrane can be used for the repair of radial nerve injury.