Background Functional disability in older adults is common and adversely impacts the quality of life. Given the paucity of population-based data, the present analysis attempted to determine the prevalence and factors associated with functional disability in basic activities of daily living (ADLs) among the elderly population in a rural setting of Northeastern state of India Methods A total of 430 elderly were recruited in a population-based cross-sectional study among elderly individuals (≥60 years) during the period 2013-2016 in rural areas of the Dibrugarh district of Northeastern India. The Barthel index was used to measure ADL. Anyone with a Barthel index score <100 (or having limitations in one or more ADL items) were considered as having a functional disability. The analysis of variance (ANOVA) test and the binary logistic regression analysis were used to examine the factors associated with functional disability. Results Overall, 43.7% % (Male 42.9%, Female 44.5%) of the participants had a functional disability. Increasing age, being widowed, having no formal education, being underweight (body mass index (BMI)<18.5 kg/m 2), and increasing numbers of morbidities were significantly associated with functional disability among the elderly in this study in age and gender-adjusted logistic regression analysis. Being ≥80 years was associated with a threefold greater risk (OR=31.72, 95% CI=1.3-6.91) of functional disability than the youngest age group (60-69 years). On the other hand, the presence of more than five morbidities was associated with a nearly 20 times increased risk (OR=19.61, 95% CI=9.01-42.68) than those with zero to two morbidities. Conclusion A high proportion of the rural elderly residents of Dibrugarh had a functional disability. The study provides epidemiological evidence of the risk factors of functional disability in this setting. This epidemiological information may be useful for developing prevention strategies to reduce the burden of functional disability.