At the international level and in Africa, since the world food crisis of 2007-2008, many actors, who throw themselves into the fight against food security, have been discussing agricultural development models. In this context, those actors are organizing their advocacy and political position using many concepts, such as a family farming, sustainable agriculture, ecological agriculture, sustainable intensification of agriculture, or organic agriculture. This thesis is looking specifically at the Organic Agricultural Model, its sociological origins and its progressive institutionalization on the African continent. This research aims to study: (a) the emerging process of the organic agricultural model in Africa (in others words the diversity of actors’ visions regarding this model, which actors are defending those visions, and the possible struggles between actors), and (b) the links between the debates regarding those visions and public decisions, or the process and the forms taken during the institutionalization. In order to do that, we mobilize a francophone public policy approach, combine with recent work on public action in Africa. In order to answer those questions, we would like to explore two countries which represent the institutionalization of two different visions of organic farming in Africa: the emergence and development of non certified organic agriculture in Benin, and the certified organic agriculture in Uganda.