Abstract: Objective To observe the changes of molecular markers of blood coagulation and hemostasis in old patients with unstable angina pactoris(UAP),and to investigate the clinical significance.Methods Fourtytwo old patients with UAP were enrolled as patient group.18 volunteers were enrolled as control group.The levels of vWF,ATⅢ,Plg,GMP-140,Fbg,D-Dimer and molecular number GP were measured in both groups.Results Compared with control group,there were significant changes of molecular number GP,vWF,GMP-140,Plg,D-Dimer,ATⅢ in old patients with UAP(P<0.05,P<0.01).Conclusion There is pre-thrombotic state in old patients with UAP.Many factors in blood may help develop coagulation and hemostasis,resulting in myocardial infarction as well as vascular disease.