Abstract: Objective: To study the clinical significance of plasma D-dimer and fibrinogen levels in diagnosis of malignancy. Methods: The plasma D-dimer and fibrinogen levels were tested in 60 common malignancy patients and 30 healthy cases as control by German Sysmex CA-1500 auto coagulative instrument. Results: Compared with control group, the plasma D-dimer and fibrinogen levels in malignancy patients' were increased obviously(P ＜ 0. 01) . There was no statistical difference about plasma D-dimer and fibrinogen positive rates among the common five cancers(P ＞ 0. 05) ,but had significant difference with control group(P ＜ 0. 05) . Conclusions: Malignancy patients have the secondary different degree of fibrinolysis,plasma D-dimer and fibrinogen levels are able to facilitate the diagnosis of malignancy.