Over the last two decades, childhood obesity has emerged as a major public health issue in Switzerland. Health professionals and public health organisations now frame this condition as a disease that requires medical intervention. In this article, I report the findings of an ethnographic study conducted in a Swiss hospital program for the management of childhood obesity. The study explored the impact of the medical treatment of childhood obesity on children's lives. Using a Bourdieusian approach to guide my analysis, I found that the experience of the therapy varies substantially according to children's socioeconomic position. Children with a high SES seem to encounter less difficulties in adapting their lifestyle to professionals' recommendations than low SES children, because their habitus facilitates the internalisation of health norms and they have greater access to economic, social and cultural capitals. Therefore, childhood obesity management tends to reproduce health inequalities between children.