Objective To investigate the feasibility of transplantation of mesenchymal stem cell (aisc) into expanion skin. Methods MSCs were isolated from porker's bone marrow and cultured in vitro. Pigs were randomly divided into four groups: Group A was injected with MSCs on the local expansion; Group B was injected with MSCs from ear vein; Group C was planted expander only; Group D was the contronl group. Each side of pig's spinal column was implanted with three expander in groups A, B and C. The same volume of NS was injected at the fixed time, the marked area measured after 7, 14, 28 days of expansion, the difference of those area was compared between groups. The differentiation of BM-MSC was detected by immunofluorescence. Results Flow-cytometric analysis showed that these BMSCs expressed CD90 and CD29 highly but did not express CD34 or CD45. The expansion area (cm2) of groups A, B, C and D was 34.05±0. 92, 31.83±l. 07,30. 10±0.79, and 18. 27±0.25, respectively (P＜0. 01). Immunofluorescence showed that the positive expression rate of CD31, PCNA in groups A and B was higher than that in groups C and D, in which the expression was the highest in group A. Conclusions Allogeneic transplantation of BM-MSC can promote skin expansion and the effect of local transplantation group is most significant.