VWF factor is a vascular hemophilia factor. This factor is mainly produced by the endothelial cells of blood vessels and plays an important role in the physiological hemostasis of the body. The specific mechanism of action is that VWF factor can adhere to the endothelial cells of blood vessels and on the other hand to the glycoproteins of platelets, which enables platelets to adhere to the endothelial cells of blood vessels through VWF factor and thus perform hemostatic functions. If VWF factor is deficient, the ability of platelets to adhere to the endothelial cells of blood vessels is reduced, and bleeding symptoms are likely to occur. Clinically, in case of hereditary VWF factor deficiency, which is a vascular hemophilia, the patient will show obvious bleeding symptoms, manifesting as continuous bleeding after trauma, or will develop hematomas in joints and muscles, etc. VWF factor plays an important role in physiological hemostasis.