Obesity in children is considered the main childhood health problem. To assess the impact of 7-year community-based interventions on the trend prevalence of overweight and obesity in French preschool children and primary school children between 2008 and 2015. Two cross-sectional studies were performed in the last grade of every pre-school and primary schools of 6 cities in 2008 and 2015. In 2008 and 2015, 3387 children and 3415 children (aged 5 and 11 years old) participated in the 2 surveys. Interventions consisted to promote physical activity, healthy diet, sleep habits and well-being. Prevalence of overweight and obesity were defined according to age- and sex-specific BMI cut-off points. Priority education area of the schools was also recorded. Prevalence of overweight and obesity decreased significantly between 2008 and 2015 in children from pre-schools (18.1% vs 13.0%) and primary schools (20.9% vs 16.9%) (P < 0.05). No effects of priority education area and sex were found related to the decrease of prevalence in overweight and obesity. Our results show that over 7 years period, the community-based intervention has a positive impact on the overweight and obesity prevalence in childhood. These results are promising and encouraging in addressing obesity and related issues in French young boys and girls.