Abstract: Objective 　To investigation the effects of the treatment on the osteosarcoma by antisense TGF-β1 gene in vivo. Methods 　LM8 were transfected with antisense TGF-β1 gene through lipofectamine vector and selected by G418. The model of osteosarcoma was established by C3h mice which were inoculated with LM8 lines. The model tumor was treated by inactivated t ransduced and untransduced LM8 by way of original site and different site, and the treatment of PBS was applied in the group of comparison. Results 　The significant therapeutic effects was achieved by the treatment of the inactivated transduced LM8. The strong inhibition to generation rate and growth speed was exhibited. A better antitumor effect was achieved in the original site tumor compared with the different site. Conclusion 　The way of gene therapy for osteosarcoma by antisense TGF-β1 gene was feasible and effective, which provided the foundation of gene therapy for human osteosarcma.