Daibetes mellitus is a strong risk factor for heart disease. In acute myocardial infarction, plasma glucose levels on admission ( in diabetics as well as non diabetics) affect the outcome and major adverse cardiac events. We studied the relationship between stress hyperglycemia and mortality in non- diabetic and diabetic patients having acute myocardial infarction. We also tried to correlate other variables like age, sex, systolic blood pressure, serum creatinine and lipid levels on admission, with the outcome.We concluded that admission plasma sugar levels can be regarded as a strong predictor of complications and mortality after acute myocardial infarction irrespective of presence or absence of diabetes. Thus stress hyperglycemia carries as bad a prognosis as diabetes mellitus in acute myocardial infarction.