High prothrombin time activity suggests a state of hypercoagulability in the body, which can easily lead to the occurrence of blood clots. Plasminogen activity is a commonly used clinical indicator of coagulation and the most important indicator of the severity and prognosis of liver disease. Plasminogen is a protein in the blood that is synthesized by liver cells. The activity of prothrombin time is 75%~100%. When plasminogen activity increases, it suggests that the body is in a state of hypercoagulability and is prone to thrombosis. In addition, prothrombin activity can reflect the liver reserve capacity, its value <40%, suggesting that the liver compensation function is very poor. Decrease in prothrombin time and activity may also reflect the liver can not effectively remove plasma activated coagulation factors and coagulation inhibitors; hepatic synthesis of fibrinogen function is impaired; hyperfibrinolysis in the blood; the existence of diffuse intravascular coagulation. Therefore, if abnormal activity of prothrombin time is detected, further examination should be perfected to clarify the specific cause.