Objectives To evaluate the levels of total testosterone (TT), free testosterone (FT), matrix metalloproteinase-9(MMP-9),and tissue inhibitor of metalloproteinase-1(TIMP-1), soluble intercellular adhesion molecule-1 (sICAM-1), C-reactive protein (CRP)and association between them in male patients with different type of coronary heart diseases, and to assess the role they played in the pathogenesis of male acute coronary syndrome(ACS).Methods 90 patients with coronary heart disease (CHD) including acute myocardial infarction (AMI), unstable angina pectoris(UAP) , stable angina pectoris(SAP)and 30 healthy volunteers as controls were recruited. Serum concentrations of MMP-9, TIMP-1,sICAM-1 were measured with ELISA kits. CRP levels were measured with immunoturbidimetric assay, and white blood cell count (WBC) were also assessed before any treatment was administrated . Results ① The serum levels of free testosterone were significantly lower in patients with ACS (14.41±3.97 pg/mL in AMI group, 17.22±4.05 pg/mL in UAP group, and 26.49±8.72 pg/mL in control group). MMP-9 levels (257.38±37.14 μg/L in AMI, 147.91±32.47 μg/L in UAP, and 57.26±31.75 μg/L in controls) and the ratios of MMP-9/TIMP-1 (4.23±0.51 in AMI, 2.32±0.38 in UAP, and 1.02±0.32 in controls), meanwhile, were notably higher in ACS patients than those in control group(P< 0.01). ② Significant negative correlation between the serum levels of testosterone and MMP-9(-0.328 for TT, P<0.05; -0.542 for FT,P < 0.01), and MMP-9/TIMP-1(-0.309 for TT, P<0.05; -0.519 for FT, P<0.01) were observed in ACS groups. ③ The serum levels of sICAM-1, CRP and WBC in the patients with ACS were significantly higher than those in the control group (P< 0.01). Conclusions The elevation of serum concentrations of inflammatory markers including MMP-9, sICAM-1, CRP and WBC are associated with initiation and progression of ACS, while there are significant negative correlation between the serum levels of testosterone and MMP-9, MMP-9/TIMP-1. Physiological testosterone may have beneficial regulating effects on inflammation reaction. Objectives To evaluate the levels of total testosterone (TT), free testosterone (FT), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinase-1 (TIMP- 1), C-reactive protein (CRP) and association between them in male patients with different type of coronary heart diseases, and to assess the role they played in the pathogenesis of male acute coronary syndrome (ACS). Methods 90 patients with coronary heart Serum concentrations of MMP-9, TIMP-1, sICAM-1 were measured in acute myocardial infarction (AMI), unstable angina pectoris (UAP), stable angina pectoris (SAP) and 30 healthy volunteers as controls were recruited with ELISA kits. CRP levels were measured with immunoturbidimetric assay, and white blood cell count (WBC) also also before any treatment was administered. Results ① The serum levels of free testosterone were significantly lower in patients with ACS (14.41 ± 3.97 pg / mL in AMI gro up, 17.22 ± 4.05 pg / mL in UAP group and 26.49 ± 8.72 pg / mL in control group). MMP-9 levels (257.38 ± 37.14 μg / L in AMI, 147.91 ± 32.47 μg / L in UAP, and 57.26 ± 31.75 μg / L in controls) and the ratios of MMP-9 / TIMP-1 (4.23 ± 0.51 in AMI, 2.32 ± 0.38 in UAP, and 1.02 ± 0.32 in controls), meanwhile, were notably higher in ACS patients than those in control group (P <0.01) .② Significant negative correlation between the serum levels of testosterone and MMP-9 (-0.328 for TT, P <0.05; -0.542 for FT, (-0.309 for TT, P <0.05; -0.519 for FT, P <0.01) were observed in ACS groups. ③ The serum levels of sICAM-1, CRP and WBC in the patients with ACS were significantly higher than those in the control group (P <0.01). Conclusions The elevation of serum concentrations of inflammatory markers including MMP-9, sICAM-1, CRP and WBC are associated with initiation and progression of ACS, while there are significant negative correlation between the serum levels of testosterone and MMP-9 , MMP-9 / TIMP-1. Physiological testosterone may have beneficial regulating effects on inflammation reaction.