Introduction: Seasonal influenza is a common etiology of acute respiratory tract infection in children. H1N1 Influenza is a common etiology of morbidity and mortality in hospitalized children. This study is done to evaluate the risk factors for severe illness and outcome of children admitted with H1N1 influenza. Methods: This was a retrospective descriptive-analytical study done at a tertiary referral care centre in South India. The study population included hospitalized children with H1N1 Influenza during the study period of 3 years. Demographic, clinical and laboratory data was collected. Risk factors for severe illness were analyzed. Results: The study population included 88 children with H1N1 Influenza of whom 18 (20.5%) required intensive care admission. The median age of study population was 5.34years (IQR 0.6-11.4) with male: female ratio of 1.1:1. Risk factors for hospitalization included malnutrition in 28 (31.8%) children, followed by anaemia in 22 (25%), pre-existing wheeze in 12 (13.6%), pre-existing neurological illness in 9 (10.2%), congenital heart disease in 10 (11.4%), immunosuppressive state in 9 (10.2%), chronic liver disease, chronic kidney disease and kyphoscoliosis in 3 (3.4%), 2 (2.3%) and 2 (2.3%) children respectively. It was noticed that the risk of PICU admission for significantly increases in the presence of malnutrition, anaemia, NLR>2 and CRP>30 with Odds ratio of 11.5 (p<0.001), 6.53 (p<0.001), 23.8 (p<0.001) and 42.3 (p<0,001) respectively. The difference between the median levels of CRP between 2 groups was also significant (54.2 vs. 36.4, p value 0.04). Mortality was observed in 3 (3.4%) children. Conclusion: The presence of malnutrition is a significant risk factor for hospitalization. Malnutrition, anaemia, preexisting immunosuppressive status, NLR>2 and elevated CRP>30, are risk factors severe illness.