Abstract: The appearance of tissue thromboplastin (factor III, tissue factor) in the bloodstream leads to one of the most dangerous non-specific disorders of hemocoagulation - disseminated intravascular clotting (DIC). Although the components of the thromboplastin reaction are known, the molecular organization of tissue thromboplastin to the extent necessary to understand the initiation of the external pathway of the blood coagulation system has not been detailed to date.