In this study, we investigated the impact of transplantation of the crude bone marrow (CBM) directly into the bone marrow cavity of the recipients’ tibia on the survival of skin allografts across MHC barrier. A total of 54 transplantations were performed in 9 experimental groups. Crude bone marrow from the donor tibia and skin allografts were transplanted from the same donors (Lewis-Brown-Norway; LBN, RT1^l+n) donors. The BM was implanted directly into the tibia of the Lewis (LEW, RT1^l) recipients followed by the standard skin graft transplantation. Combined protocol of Cyclosporine A (CsA) and ab TCR monoclonal antibodies was used as the treatment modality for 7 days. In-group 1 and 2, which served as the controls, the skin transplantations were performed between isogenic and allogenic rat strains, with no treatment. In-group 3, skin and crude bone marrow was transplanted without immunosuppression. In-group 4 and 5, animals received skin allografts along with the monotherapy of CsA or ab -TCR mAb, respectively. In-group 6, combined treatment of ab -TCR mAb/CsA was applied to the recipients of skin allografts without CBM transplantation. In-group 7 and 8, monotherapies of ab -TCR mAb and CsA were applied along with CBM transplantation. In-group 9, the CBM and skin allografts were transplanted under combined ab-TCR mAb(250µg)/CsA(16mg/kg) treatment for 7 days only. Skin isografts (Group1) survived indefinitely. Skin allograft rejection was observed in groups 2 (Skin Allograft alone) and 3 (Skin Allograft+ CBM) at days 7 and 10, respectively, and was extended to 15 ans 12 days in group 4 (Skin allograft + CsA) and group 5 (Skin allograft+ abTCR mAb), respectively. Transplantation of CBM in group 7 (Skin allografts with CBM+CsA), and 8 (Skin allografts with CBM+ab TCR mAb) further extended allograft survival up to was 20 and 15 days, respectively (p<0.05). Finally in group 9, skin allografts combined with CBM and ab TCR mAb/CsA protocol extended transplant survival up to 65 days (p<0.05). Flow cytometry analysis revealed 12 % of donor specific chimerism (3.6% CD4+ and 6.3% CD8+ cells) in the peripheral blood of allograft recipients. In this study, transplantation of the crude bone marrow directly into recipients’ tibia resulted in significant extension of the skin allograft survival from the same donor and induced donor specific hematopoietic chimerism. This study implies that crude bone marrow transplantation may be used as a novel, minimally invasive method of enhancing allograft transplant survival.