Blood coagulation is a complex physiological process. With the development of biochemistry and molecular biology, especially the discovery of the tissue factor pathway inhibitor (TFPI) and further research, the researches of tissue factor (TF) and TFPI have been the hot topics now. Based on this result, we provide a new concept of blood coagulation system and provide a dynamic model to describe the role of TFPI of this pathway. Through stability analysis of the equilibrium point and numerical simulations, we obtain some important conclusions. All these results may have great significance for lesions of cardiac vessels and cerebral vessels, haemophilia, DIC, thrombosis formation and malignancy.