ABSTRACT. Objectives: The prevalence of obesity is highest in older persons and a correct self-perception of body weight status is necessary for optimal weight control. The aim of this study was to determine self-perception of, and satisfaction with, body weight status, and to compare current versus ideal body image in a large, nationally representative sample of older people. Furthermore, determinants of misperception were explored. Design: A cross-sectional study. Setting: The Longitudinal Aging Study Amsterdam (LASA), conducted in a population-based sample in the Netherlands. Participants: 1295 men and women aged 60-96 years. Measurements: Body weight status was assessed using measured weight and height. Self-perceived body weight status, satisfaction with body weight and current and ideal body image were also assessed. Multiple logistic regression analysis was used to investigate the association of age, educational level and objectively measured BMI with underestimation of body weight status. Results: The prevalence of obesity was 19.9% in men and 29.3% in women. The agreement between objective and self-perceived body weight status was low (Kappa < 0.2). Among overweight and obese persons, 42.1% of men and 44.1% of women were (very) dissatisfied with their body weight status and >99% of obese participants desired to be thinner (ideal body image < current image). Only 4.4% of obese men and 12.3% of obese women perceived their body weight status correctly. Higher age (women), lower educational level (men) and higher BMI (all) were associated with greater underestimation of body weight status. Conclusion: Many older persons misperceive their body weight status. Future actions to improve body weight perception in older persons are necessary to increase the impact of public health campaigns focussing on a healthy body weight in old age.