Transplantation of adipose tissue-derived stem cells (ADSCs) is a promising method that has been used in regenerative medicine because it has shown the capacity to accelerate wound healing. However, roles of ADSCs transplantation in expanded-skin regeneration have remained unknown. To clarify the roles, a tissue expansion model was used in this study. The study comprised three groups of 13 rats in each group: the ADSCs group, the fibroblast (FB) group, and the control group. The skin regeneration in the ADSCs group was enhanced, as evidenced by increased cell proliferation and a higher hydroxyproline content and degree of neovascularization, all with p < 0.05, when compared with both the FB group and the control group. Consistent with enhanced cell proliferation and neovascularization, the regenerated skin in the ADSCs group was much thicker, which further reduced the retraction ratio of the expanded skin. Four weeks after operation, 5'-bromo-2'-deoxyuridine-labeled ADSCs appeared in subcutaneous tissue, vascular vessels, and hair follicles. The up-regulation of protein expression, such as epidermal growth factor and vascular endothelial growth factor, primarily emerged in the ADSC group, with the up-regulated basic fibroblast growth factor appearing in the FB group. Collectively, these results suggest that the transplantation of ADSCs could enhance the regeneration of expanded skin by participating in skin structures and up-regulating the secretion of epidermal growth factor and vascular endothelial growth factor.