Although French and Brazilian agricultures differ notably in terms of social structuring, there are strong controversies and social conflicts in both countries between mainstream and alternative forms of agriculture. In such contexts, agroecology has progressively been institutionalized and implemented in both countries as an official paradigm for national agricultural policies – focused on family agriculture in Brazil. In the French agricultural policy launched in 2012 on the other hand it has been considered as an encompasging paradigm designed to involve all kinds of farmers and farms. In both cases, these public policies have emerged out of a process of political construction that is the result of the various interactions between different social world: social movements, the academic world, the agricultural world and policy makers. These interactions, which are characterized by different power relationships and alliances, lead to different and often antagonistic conceptions of agroecology, especially regarding two key aspects, i.e., the kind of agriculture and the kind of farmers that should be targeted, and the need to take into account the reconnection between agriculture and food at the scale of agrifood systems beyond the classical approach at farm scale and agricultural practices.