It is the purpose of this study to systematically review the evidence of school-based interventions targeting dietary and physical activity behaviour in primary (6-12 years old) and secondary school (12-18 years old) children in Europe. Eleven studies (reported in 27 articles) met the inclusion criteria, six in primary school and five in secondary school children. Interventions were evaluated in terms of behavioural determinants, behaviour (diet and physical activity) and weight-related outcomes (body mass index [BMI] or other indicators of obesity). The results suggest that combining educational and environmental components that focus on both sides of the energy balance give better and more relevant effects. Furthermore, computer-tailored personalized education in the classroom showed better results than a generic classroom curriculum. Environmental interventions might include organized physical activities during breaks, or before and after school; improved availability of physical activity opportunities in and around the school environment; increased physical education lesson time; improved availability or accessibility of healthy food options; and restricted availability and accessibility of unhealthy food options. More high-quality studies are needed to assess obesity-related interventions in Europe.