OBJECTIVE To determine the frequency of risk factors in male patients presenting with acute coronary syndrome. STUDY DESIGN Observational study. PLACE AND DURATION OF STUDY Armed Forces Institute of Cardiology and National Institute of Heart Diseases, Rawalpindi, from October 2007 to September 2008. METHODOLOGY Male patients with acute coronary syndrome were included in this study. Patients having angioplasty (PCI), coronary artery bypass surgery, chronic liver and kidney diseases were excluded. Presence of diabetes, smoking, hypertension, dyslipidemia, physical activity, stress, a family history of coronary artery disease (CAD) and medication was documented. Blood pressure, ECG, cardiac enzymes, fasting blood glucose, lipid profile and echocardiography were done within 24 hours of admission. Body mass index and waist circumference were measured. Data was analysed using SPSS-15. RESULTS A total of 135 male patients of ACS were studied having mean age of 54.26±11.60 years. Maximum number of patients aged between 51 to 60 years, (n = 41, 31.9%). STEMI (ST-elevation myocardial infarction) was diagnosed in 96 (71.1%) patients, non-STEMI in 12 (8.9%) while 27 (20%) patients were having unstable angina. Smoking was documented in 60 (44%) patients, hypertension in 50 (37%), diabetes in 34 (25.2%) and a family history of premature CAD was recorded in 24 (17.8%) patients. Fifty one (37.8%) patients were overweight (BMI = 25-29.9) while 22 (16.3%) were obese (BMI ³ 30). Waist circumference > 90 cm was found in 86 (63.6%) subjects. Sixty four (47.4%) patients were active physically. Psychosocial stress was documented in 33 (23.75). Hypertension, diabetes and dyslipidemia were the most frequent combinations, observed in 24 (17.9%) subjects. CONCLUSION Dyslipidemia, smoking, hypertension and diabetes were most frequent risk factors. Public awareness to control risk factors can reduce the prevalence of CAD.