Background: Despite advances in the management of acute respiratory failure with mechanical ventilation, mortality has not decreased significantly and the cost still remains high. Knowledge of the epidemiology of patients requiring mechanical ventilation, including mortality rates and mortality risk factors, may help to improve therapeutic strategies, as might counselling of patients or their relatives. Material and method: A cross–sectional observational study was conducted for duration of 2 years to asses’ clinical profile of patients on invasive Mechanical ventilation in medical Intensive Care Unit of tertiary care centre. A proforma was designed to collect the desired information from the patients. The preformed structured proforma consisted of recording of investigations was used as data collection tool. Results: Majority of patients belonged to the age group of 56–65 years with male predominance. M:F –1.7:1. Majority of patients in the present study required mechanical ventilation due to complicated pneumonia (35) followed by ARDS (28) and cardiogenic pulmonary oedema (11). VAP was the most common complication (26%) seen in the present study.