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.