A study was undertaken amog 80 non-diabetic patients of acute myocardial infarction (AMI) admitted within 24 hours of the onset of pain, to investigate the prevalence and significance of microalbuminuria (MA) as a predictor of in-hospital mortality, and also to correlate it with other well-established prognostic markers. Spot urinary albumin-to-creatinine ratio (ACR) was measured in first morning sample on day 1 (D1), day 4 (D4) and/or day 7 (D7). Haemodynamic status was assessed clinically by Killip's class and the ejection fraction was measured by echocardiography on D1, D4, and/or D7. Total 7 days mortality was recorded. MA (>30 microg/mg) was found in 95% of patients on 1,. In the group with higher value of MA (>100 microg/mg) on D1, there was significantly more deaths (p <0.01). Also there was significantly more deaths with static or increasing MA value from D1 to D4/D7 (p <0.01). Increasing or static MA had a positive correlation with deteriorating Killip's class in non-survivors, and also there was a correlation between decrease in left ventricular ejection fraction from D1 to D4/D7 and an increasing trend in MA over that period. Thus, MA was found to be a reliable predictor of short-term in-hospital mortality in AMI.