Reconstruction of large scale skin defect is a challenge to clinical surgeons. Soft tissue expansion has won wide attention in recent years as it promotes skin regeneration with perfectly matched tissue. However, some patients with poor skin regenerative ability would suffer from skin flap over-thinned and even necrosis under the continuous stretching by silicone expander. Although, on some occasions, decelerating the expander inflation process could reduce the incidence of necrosis, this prolonged therapy circle is to be accompanied with increased complications, including infection and expander rupture, as well as the increased economic expenses by the longer hospitalization. This study is to observe the effects of autologous bone marrow mononuclear cell transplantation on accelerating skin regeneration and promoting tissue expansion process.