Incidence of coronary artery disease (CAD) is increasing in developing countries in Bangladesh with improvement of socioeconomic status, urbanization, changes of dietary habits and lifestyle. Dyslipidaemia is one of the major contributors increase CAD risk. This study was aimed to find out the association of low level HDL-C with acute coronary syndrome. This cross sectional study was conducted in the department of cardiology, Mymensingh Medical College Hospital, Mymensingh, Bangladesh from August 2009 to May 2010. Sociodemographic characteristics, smoking, hypertension, FBS, serum total cholesterol level, HDL-C, LDL-C, Triglyceride level were important variable considered. A total number of 100 respondents consisted of 50 cases (patient) Group I and 50 healthy people (control) Group II. Investigations included ECG, Troponin-I, FBS and Fasting Lipid Profile. The data was analyzed by computer with the help of SPSS. Chi-square test, T-test, ANOVA test used as test of significance. The mean level in cases of HDL-C 39.3±5.1 and in control level HDL-C 34.2±3.4 statistically significant (p<0.0001). In both group low concentration HDL-C (<40mg/dl) risk for CAD. Un-adjusted odds ratio 95% CI determinants of ACS, HDL-C of OR was 0.2. So, HDL-C is not protective factor. In multivariate logistic regression analysis that adjusted for confounders of HDL-C level (age, sex, smoking, hypertension, TC, LDL-C, TG) associated with ACS. HDL-C was strong predictor of ACS (RR in the highest) compared with lowest quarantile = 0.02; (95% CI=0.003-0.173; P for trend <0.0001). The study reflected that low HDL-C level associated with ACS. Categorization of patients with ACS on the basis HDL-C level may be helpful for risk stratification and management.