Background: Pre-treatment Body mass Index (BMI) is an important prognostic factor in HNC with variable survival benefit reported till date. Despite increasing incidence of HNC in geriatric patients there is limited information on prognostic variables in this group. Methods: This is a single center, retrospective cohort study of patients with HNC≥65 years of age at their diagnosis from 2012 to 2016. Patients were stratified by BMI (Class 1- BMI<25 kg/m² (underweight & normal), Class 2- BMI≥25-29.9 kg/m² (overweight), Class 3- BMI≥30 kg/m² (obese) ). Various variables were collected & appropriate statistical analysis was done. Results: 188 elderly HNC patients with non-metastatic disease were stratified into three BMI groups (Table) & found to have evenly distributed co-variates. The Median OS was significantly higher in class 3 patients (53 months) compared to class 1 (21 months) (p =0.02). In multivariate analysis, class 3 was an independent good prognostic indicator (Hazard ratio=0.44;Range-0.21-0.90, p=0.03). Stage, CCI score & gastrostomy tube were adverse prognostic factors in the study. Conclusions: Obese elderly HNC patients have survival benefit over normal/underweight patients. Predictive prognostic models incorporating BMI with other prognostic factors are needed to determine appropriate management in these patients.