The purpose of this article is to show how the action carried out in Millau (South of France) in summer 1999 against a Mac Donald's by sheep breeders in the country of Roquefort is linked with the story of left-wing trends in peasants'unions. The Confédération Paysanne was born in 1987 from several left-wing unions of peasants. This union tries to defend small farmers and to practice a sustainable agriculture and development. Solidarity is the most important value of his project. This action became an important political event because this union called up to mobilize but also because the medias support José Bové and the ideas of this union. The reason is that this project seems to answer to the problems of agriculture at this end of the 20th century. This point of view help the Confédération Paysanne to support José Bové and his ideas.