Resumo. ABSTRACT This study aimed to investigate body dissatisfaction among adolescents in social vulnerability and to verify possible associations with self-reported and measured anthropometric data (weight, height and BMI). A total of 204 adolescents participated, being 78 girls and 126 boys aged 10 to 14 years old (11.9+1.55). Body weight and height were measured and self-reported. Body dissatisfaction was assessed by the Brazilian Silhouette Scale for Children. Body dissatisfaction levels were found (82.8%) in both sexes, wherein girls and boys did not differ as to dissatisfaction (p=0.10). In both sexes, measured body mass (p=0.05 in girls; p=0.0339 in boys) and height (p=0.0086 in girls; p=0.0001 in boys) were significantly different from self-reported body mass and height. Body dissatisfaction related positively and significantly to measured BMI (r=0.55, p<0.0001), but not to self-reported BMI (rs=-0.0324, p=0.645). In conclusion, self-reported measures did not represent measured data realistically and should be used with caution in future studies addressing body dissatisfaction among adolescents in social vulnerability.