Ten mature rabbits was used in this study. The animals were divided into two equal groups. Femoral mid–shaft fractures were induced, and destruction of both periosteum and endosteum for about one centimeter around the fractured ends was performed. The fractured bone was immobilized by intramedullary pinning. Group 1 considered as control, while group 2 was implanted by sufficient amount of auto–bone marrow at the fracture site. The radiographic results revealed that, the destruction of both periosteum and endosteum leads to delayunion and some percentage of nonunion. While the bone marrow in group two promoted and enhanced the fracture healing.