Background: Obesity is related to underestimation of one’s ownweight. Aim: To determine the agreement between nutritional status and self perception of weightstatus in apparently healthy adults from Talca. Subjects and methods: Data were obtained froma survey applied at 1007 randomly selected subjects, aged 18-74 years old (66% women). Thesurvey identified age, gender, educational level and socioeconomic status. Self-perception ofweight was estimated with pictures representing the four nutritional status categories:underweight, normal, overweight and obese. Body Mass Index (BMI, kg/m2) was calculated todetermine nutritional status. Statistical analysis included kappa index, Bowman’s symmetry testand a logistic regression model to calculate the odds ratio in different variables related tounderestimation of weight. Results: Seventy three percent of subjects were overweight or obeseand 44% underestimated their nutritional status. Sixty percent of subjects with a BMI between 25and 26 kg/m2, perceived themselves as normal. A higher underestimation was observed in obesesubjects (odds ratio (OR) 17.2 95% confidence intervals (CI) 10.9-27.1), in overweight individuals(OR 3.5 95% CI 2.3-5.3), in men (OR 1.5 95% CI 1.1-2.1) and in people aged from 45 to 59 years(OR 1.7 95% CI 1.0-2.7). Conclusion: Almost half of studied population had an erroneous selfperceptionof weight, mainly due to underestimation. Obese subjects, males and people older than45 years were those with the higher degree of underestimation