Background: The 2009 flu outbreak in humans, known as "swine influenza" or H1N1 influenza A, refers to influenza A due to a new H1N1 strain called Swine-Origin Influenza Virus A (S-OIV). Global pandemics with high mortality and morbidity occur when a virulent new viral strain emerges. Aim and Objectives: To study demography, clinical profile and outcome of H1N1 influenza infection at a tertiary care teaching hospital. Material and Methods: This was a prospective observational study conducted at the teaching hospital during six month period. It was a time bound study over a period of six months (from 1st July 2018 to 30th December 2018). All suspects with throat swab/nasal swab positive for influenza H1N1 virus by Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) with age more than 15 years were included in the present study. Data were analysed for mean, percentage, standard deviation and Chi square test for quantitative data by using Microsoft Excel spread sheet. Results: A total 60 patients were admitted with confirmed diagnosis of H1N1 infection. Out of the 21 (35%) were males and 39 (65%) were females,predominated by female gender (p=0.001). The mean age in male (46.14 ± 20.058) was relatively more compared to female gender (36.33 ± 11.50). The male gender had more co-morbidities and risk factors compared to female patients (p=0.01) and was statistically significant. Out of total 21 male patients 7 patients died because of bilateral pneumonia and Acute Respiratory Distress Syndrome (ARDS) and Multi-Organ Dysfunction (MOD) with case fatality rate of 33.33%. Out of total 39 female patients 5 patients died with case fatality rate of 12.82%. Conclusion: The present study highlighted the disease burden associated with H1N1 infection. The advancing age, male gender, associated co-morbidities and delayed presentation were the risk factors for mortality in present cohort study of H1N1 patients. The community awareness, early case detection and timely management can reduce the disease burden at large.