Objective To explore the changes in plasma tissue factor(TF),tissue factor pathway inhibitor(TFPI),interleukin-18(IL-18),and interleukin-10(IL-10) in patients with coronary heart disease(CHD),and to investigate their roles in the development of CHD and their mutual relationships. Methods A total of 121 patients were divided into control group (n=25) and CHD group (n=96). CHD group was further divided into acute myocardial infarction (AMI) subgroup (n=33),unstable angina pectoris (UAP) subgroup (n=33) and stable angina pectoris (SAP) subgroup (n=30). Plasma TF,TFPI,IL-18,IL-10 levels were detected by enzyme-linked immunosorbent assay (ELISA). Results The plasma concentrations of TF,TFPI and TF/TFPI ratio were higher in CHD group than in control group; they were higher in AMI subgroup than in UAP and SAP subgroups,and higher in UAP subgroup than in SAP subgroup. The plasma concentrations of IL-18,IL-10,and IL-18/IL-10 ratio in CHD group were higher than those in control group. The plasma concentrations of IL-18 and IL-18/IL-10 ratio were higher in AMI subgroup than in UAP and SAP subgroups,and higher in UAP subgroup than that in SAP subgroup. The plasma concentration of IL-10 in AMI and UAP subgroups was lower than that in SAP subgroup. In CHD group,plasma TF was positively correlated with IL-18 (r=-0.302 2,P<0.01) and TF/TFPI ratio was also positively associated with IL-18/IL-10 (r=0.3494,P=0.01). Conclusion Hypercoagulability activity and high inflammatory response exist in CHD patients; further more,they parallel with the severity of the disease. The positive relationship between coagulation factors and inflammatory factors suggests that they play an important role in the development of CHD and be used to evaluate the severity of the disease.