To investigate the mechanism of chemotherapy related DIC, a quantitative and comparative study was carried out on the coagulation activities of minor cells and tumor tissues in three strains of rat ascites hepatoma AH109A, AH272 and LY80. The content of thromboplastin was expressed as the relative concentration against that in the brain tissue. Ascites hepatoma cell and tissue of each strain obviously have different quantities of coagulants, such as tissue thromboplastin. Coagulation activities of tumor tissues are higher than that of tumor cells. The coagulation activities of tumor tissues and cells of AH272 were higher than that of AH109A and LY80. Our findings suggest that the initiation of DIC not only depend on the tissue thromboplastin, the other factors or the other mechanisms should be considered.