Objective To explore the effects of bone marrow mesenchymal stem cells (BMSCs) transplantation on Schwann cells after peripheral nerve injury. Methods BMSCs were isolated from SD rats and cultured. Injury model of the sciatic nerve cross-sectional was established, and BMSCs were injected into the distal of injured sciatic nerve. HE staining and immunofluorescence staining were used to detect the morphology and quantity of Schwann cells. Results According to HE staining and immunofluorescence staining, after BMSCs was implanted, the number of Schwann cells in sciatic nerve increased, the cell structure was more clear and complete, and the arrangement was more orderly. Conclusion BMSCs transplantation can protect Schwann cells after sciatic nerve injury.BMSCs may be a candidate in cell transplantation therapy for peripheral nerve injury.