BACKGROUND Hyperglycaemia, in both diabetic and nondiabetic patients, has a significant negative impact on the morbidity and mortality of patients presenting with an Acute Myocardial Infarction (AMI). Contemporary evidence indicates that persistent hyperglycaemia after initial hospital admission continues to exert negative effects on AMI patients. There have been a number of studies demonstrating the benefit of tight glucose control in patients presenting with AMI, but a lack of convincing clinical data ha s led to loose guidelines and poor implementation of glucose targets for this group of patients. MATERIALS AND METHODS 100 patients who came with Acute Coronary Syndrome who had admission time hyperglycaemia during October 2012 to September 2014 were studied in this study. Hyperglycaemia was defined in the current study as random blood glucose at admission more than 200 mg/dL. We studied patients of more than 18 years of age who were diagnosed as Acute Coronary Syndrome-ST Segment Elevation Myocardial Infarction (STEMI), Non-ST Segment Elevation Myocardial Infarction (NSTEMI) and Unstable Angina (UA). RESULTS Mean age for diabetic patients was 57.40 years and for non-diabetic patients was 56.09 years. Males were more susceptible to develop ACS in both the groups. Incidence of STEMI and NSTEMI was more in diabetics than non-diabetics. Incidence of Unstable Angina was more in non-diabetics than diabetics. CONCLUSION Incidence of complications is higher (surprisingly) in non-diabetics as compared to diabetics. Incidence of death is much higher in diabetics as compared to non-diabetics with stress hyperglycaemia (on admission). Hence, blood glucose level and HbA1c levels should be routinely measured in every patient with Acute Coronary Syndrome.