During evaluation period, 2009 H1N1 influenza caused severe illness requiring hospitalization, including pneumonia and respiratory distress and co-morbid condition. Maximum patients were between age group of 14-50 year. Fever and cough were most common presenting symptoms. Nearly 36.36% patients had one or more underlying medical conditions. Mechanical ventilatory support had role in reduction in mortality. Patients seemed to be benefited from antiviral therapy if started within 72 hour of onset of symptom. There were no significant side effects of Oseltamivir observed in this study. Development of ARDS, requirement of Mechanical ventilation and having co-morbid condition were poor prognostic factors. We observed two peaks of H1N1 during this period second peak was less severe than first one. It may be due to development of immunity, Disease awareness, early diagnosis and treatment and health education.