This study aimed to describe the discrepancy between body satisfaction change and weight change among adolescents following a 2-year school-based intervention, to identify associated sociodemographic factors, and to explore possible associations with perceived health indicators. We used data from a northeastern France representative adolescents sample (14-18 years old) who participated in the PRALIMAP (PRomotion de l'ALIMentation et de l'Activité Physique) study (2006-2009). Weight change was measured by the change in body mass index z-score from the start to the end of the study. Body satisfaction and self-perceived health (anxiety, depression, eating disorder and quality of life) changes were assessed using self-administered questionnaires. Discrepancy between body satisfaction change and weight change was described with cross-tabulations, and subdivided into optimism/pessimism (i.e. positive/negative body satisfaction change compared to weight change). Sociodemographic factors associated with discrepancy were determined by multivariate logistic regression models. Adjusted linear regression models described 2-year change in weight and self-perceived health according to discrepancy. Among the 3279 adolescents included (aged 15.1 ± 0.6 years), the proportion of discrepancy was 74.8% (pessimism = 41.6%; optimism = 33.2%). Discrepancy, especially pessimism, was higher in boys than in girls (OR = 1.44 [1.19; 1.74], p = .0002), and in socially advantaged adolescents (OR = 1.82 [1.20; 2.74], p = .004) than in disadvantage ones. Body satisfaction change was rather in line with anxiety, depression and quality of life changes than weight change. Body satisfaction change should be considered in overweight and obesity prevention interventions alongside body weight change, and could be used as indicator of long-term behavior maintenance. Clinical trials registry and number: ClinicalTrials.gov (NCT01688453).