Objective:Dynamically observe the serum D-dimer level of patients wit h thrombus, for instructing drug therapy and judging prognosis.Methods: Detect serum D-dimer level by latex agglutination in 113 cases, among these 20 cases were normal(control group), and 93 cases were patients with thrombus(patient g roup).Results:Detecting results of control group were all negative, positive rate of patient group were 67%～100% according type of disease.Conclusion:Level of serum D-dim er is obviously increase in patient with thrombus. It's ideal detecting index of patient with thrombus.