Ameloblastoma is a rare, benign tumor found in the jaw. These tumors have a tendency for locally aggressive expansion, and thus require surgical removal. For the previous 3 decades, autologous bone grafting and free flap surgeries have been most commonly used to correct bone defects after surgical removal of the lesion. In this report, the authors describe a case of unicystic ameloblastoma in a 14-year-old girl who was successfully treated with mandibular regeneration, attained by autologous human bone marrow mesenchymal stem cells without any autologous bone graft and free flap transfer. This case shows that autologous human bone marrow mesenchymal stem cells can be used as an alternative method to autologous bone graft and free flap transfer in a large bone defect of the jaw.