Background: Inflammation has been known as important cause of plaque rupture in acute coronary syndrome (ACS). The evaluation for saliva has been informative to general health conditions including cardiovascular disease. The purpose of this study is to investigate the salivary proteomics and inflammatory biomarker in patients who had ACS. Methods: Twenty four patients who were received diagnostic coronary angiography from Aug 2007 to Dec 2007 comprised the study group. The conditions which are known as having different salivary compositions such as old age (> 60 years) or diabetes mellitus were excluded. We divided two groups according to the existence of ACS: group I (14 patients, 54.1짹5.9 years, patients who had ACS – 8 acute myocardial infarction, 6 unstable angina) and group II (10 patients who had stable angina, 54.9짹6.5 years). Results: Baseline clinical and cardiovascular risk factors were not significantly different between the 2 groups. The laboratory findings were not significantly different between the 2 groups except salivary hsCRP (Group I: Group II = 7.1짹6.8ng/mL: 2.5짹1.7ng/mL, p=0.028) and blood neutrophil count (Group I: Group II = 4525.6짹337.7/關L: 3614.5짹221.0/關L, p=0.042). Salivary proteonomic analysis by 2D-electrophoresis showed different 9 spots between the 2 groups. The mass spectrometry showed three spots of kallikrein-1, two spots of pro 2044, two spots of albumin, poly-Ig receptor, and haptoglobin 2. Both salivary and serum hsCRP at 3-month follow up were not significantly different between the 2 groups. Conclusions: Salivary hsCRP was increased in patients who had ACS. Moreover, there were differences in the salivary proteonomics. Further investigations are needed to clarify the clinical usefulness of these new biomarkers in ACS patients.