Résumé : This paper investigates the participation in social networks of theater's audiences. Our purpose is to observe, describe and understand the role of social networks in the consumption behavior of the theater field. In particular, we put the accent on the concept of cultural capital with its social dimension. We realize an exploratory study that consists in a dozen of qualitative semi-structured interviews with theater’s audiences that participate in social networks. We provide an analytical framework in which we present information about uses, influences and perceptions of changing in social stratification in theaters. We reveal two kinds of perception: a positive one and a negative one that we denominate "democratization effect” and "vulgarization effect”. Our findings can help cultural institutions to have a better understanding of who are the actual theater audiences and how do they act. On an operational level, our study offers information to art's managers interested about the strategic use of Web 2.0 tools.