Introduction: The objective was to describe the prevalence of obesity and underweight among older adults living at home in France and to examine their association with loss of independence. Methods: The national Handicap-Santé survey, “household” component, conducted in 2008, included face-to-face collection of sociodemographic and anthropometric data, as well as data on restrictions in activities of daily living. The relationships between body mass index (BMI) categories and loss of independence (at least one activity restriction) were analyzed using multivariate logistic regressions adjusted for sociodemographic characteristics. Results: The analyses included 4,296 older adults aged 75 and older. The prevalence of underweight (BMI < 21) was 14.9% [13.3–16.7]. It was higher among women (19.6%) than among men (7.6%) and increased with age (p < 0.03). The prevalence of obesity (BMI ≥ 30) was 14.6% [13.1–16.2]. It decreased with age (p < 0.03). Among men, the risk of loss of independence was increased in cases of underweight (ORa=2.7; p=0.007) or obesity (ORa=1.9; p=0.005) compared to normal weight. Among women, the risk increased in cases of overweight (ORa=1.7; p=0.003) or obesity (ORa=2.9; p<0.003) compared to normal weight. Conclusion: Obesity and underweight are common among older adults living at home and are associated with an increased risk of loss of independence. In a context marked by an aging population and rising obesity rates among young adults, nutritional monitoring of older adults is a major public health issue. (R.A.)