Background: Hospital acquired infections are a worldwide phenomenon and infection rates in ICU__ampersandsign#39;s have been documented to be ranging from 12% to 45%. Methods and Material: To study epidemiology of nosocomial infections and its clinical outcome. Study Design and Setting: It is a prospective observational study; carried out in the Medical intensive care unit (MICU) of a tertiary care teaching hospital. Results and Conclusion: 205 patients developed nosocomial infection. The commonest nosocomial infections developing in MICU were ventilator associated pneumonia (VAP); hospital acquired pneumonia followed by urinary tract infection. 94.1% isolates were gram-negative and gram-positive contributing to 2.5%, of which most common organisms isolated were Klebsiella, Acinetobacter and E. coli. 93.4% of blood stream infections were associated with intravenous lines, 68.1% of pneumonia with intubation, 91.7 % of UTIs were associated with urinary catheter. As number of risk factors increase, like duration of mechanical ventilation, prolonged ICU stay (60.0%), increasing age, and number of organs failed, mortality increased significantly. Sensitivity of E.coli isolates to carbapenams, polymyxin was 100%. Klebsiella and Acinetobacter showed a maximum sensitivity to carbepenem, polymyxin followed by piperacillin-tazobactum. 75.1% of patients with nosocomial infections improved and mortality in current study was 30.3%.v