Abstract: Objective:To establish a model of inducing bone marrow formation with transplanting the heterogeneous demineralized bone matrix into Spraque-Dawley rat's bilateral abnominal subcutaneous tissue,to explore the mechanism of bone marrow formation and modulation.Methds:To transplant the heterogeneous(human) demineralized bone matrix into Spraque-Dawley rat's abdominal subcut-aneous tissue.Results:On 3rd to 10th day,mesenchymal cells proliferated,differentiated to immature cartilage cells and formed cartilage tissue.On 11th-21th day,primary bone marrow tissue formed.On 22th-34th day,typical bone marrow tissue appeared and a great quantity of hematopoietic cells were seen.On 4oth-60th day, no obvious atrophy of the induced hematopoitic tissue was seen.Conclusion:Bone inducing active factors of human and rat is homology.There is no herterogeneous.This model provides a new methord to study the mechanism of the formation and the modulation of bone marrow for clinical hematology.