Objective To study the effects of mild hypothemia therapy on coagulatic-fibrinolytic functions of the severe head injury patients.Methods 35 severe head injured patients from Jan 1998 to May 2000 were treated by mild hypothermia therapy and compared with past 30 patients.All patients's coagulate and fibrinolytic index was measured.Results All patients have coagulate- fibrinolytic disorders, mild hypothermia therapy can reduce consume of coagulate factors and inhibit secondary fibrinolytic function.Conclusion Mild hypothermia therapy is important to the severe head injury patients.