Objectives: This study investigated the correlation between homocysteine levels in patients with Acute Coronary Syndrome andGRACE Score.Methods: This study included 191 cases -140 Non-ST MI cases and 51 MI with ST-elevation cases in Şişli Etfal Training and ResearchHospital Coronary Intensive Care Unit between December 2008 and March 2010. Homocysteine was measured by immulite 2000device, using kemiluminesans method and competitive immunoassay principle and a kit by DPC was used during the measurement.The reference range given by the producing company was between 5-15 Mmol/L for male and female adults. The patients were classifiedinto three risk groups as low, medium and high on the basis of the criteria identified in GRACE risk score: age, heart rate, systolicblood pressure, serum creatine levels, Killip classification, cardiac arrest on admission, increased cardiac enzymes and ST segment depression.The relation between homocysteine levels in patients with Acute Coronary Syndrome and GRACE risk score was evaluated.Results: In the Non-ST MI group, a statistically-moderate positive correlation was seen between homocysteine and GRACE riskscore during the study (p<0.05). However, in the MI with ST-elevation group, no correlation was found between homocysteine andGRACE risk score (p>0.05). Overall, despite the low figures, a meaningful positive relation was observed between homocysteineand GRACE risk score in all cases.Conclusion: Homocysteine is independent of other classic risk factors for cardiovascular diseases. Therefore, we believe that routineplasma homocysteine levels should be checked when evaluating risk factors for Atherosclerotic Coronary Artery disease.