In Western societies, a lower educational level is often associated with a higher prevalence of overweight and obesity. However, there may be important international differences in the strength and direction of this relationship, perhaps in respect of differing levels of socio-economic development. We aimed to describe educational inequalities in overweight and obesity across Europe, and to explore the contribution of level of socio-economic development to cross-national differences in educational inequalities in overweight and obese adults in Europe.