The aim of this paper is to test the hypothesis that the opening of a European political space and the Europeanization of parties create a favourable arena for populist speech, themes and perhaps ideology, especially in the case of anti-EU parties. To do this, a quantitative study of populist speeches in French pro- and anti-EU party Euromanifestos has been conducted for the 1999 and 2004 European elections. It contributes to the scientific debate regarding the possible rise of a new political cleavage resulting from the European issue. Our comparative content analysis based on a coding system of populist discourse shows that there are no systematic links between the position of French parties towards the EU and their use of populist arguments, but a variety of relations, linked to the position of the parties within the party system as well as to the right/left cleavage. European issues are integrated in the ideologies and identities of the parties and only produce moderate effects on populist speeches. Therefore, party practices and speeches are stable. In some cases, what is evidenced is not a rise or a transformation of populist discourse, but national discourse patterns adapted to a European context and a phenomenon of Europeanization of certain populist themes.