Abstract: Introduction: In April 2009, a new strain of Influenza virus A H1N1, commonly referred to as "swine flu," began to spread in several countries around the world. Maharashtra state, including the Nagpur region, also started monitoring and surveillance activities as soon as the positive cases were first reported in August. We investigated these cases of influenza like illness (ILI) to confirm the A H1N1 among patients admitted in a tertiary care hospital. Methods: The present study was a cross-sectional study of successive, suspected and confirmed H1N1 patients with respiratory complication admitted to swine flue ward and ICU of a tertiary care centre from January to December 2012 at Government Medical College and Hospital, Nagpur. All cases were RT-PCR confirmed at National Institute of Virology, Pune, Maharastra.