The purpose of this paper, in contrast to the mainstream EU scholarship, is to expose the other, much less studied and potentially darker side of the EU constitutionalism. It therefore asks a question about the constitutional pitfalls for European integration. Relying on a social constructionist approach following which the current state of EU legal affairs is a product of the dominant constitutional narrative, it examines whether and to what an extent constitutionalism as a dominant narrative is itself a source at least of some of the problems that haunt the integration. The paper thus proceeds on a hypothesis that if practices of integration do not deliver as they should, this must be due to the guidance of the dominant narrative. For any practice that is based on the wrong narrative can not be but self-defeating. To prove this hypothesis the contours of the dominant constitutional narrative will be examined first. It will be explored how the integration appears in the light of the constitutional narrative and why and where the constitutional narrative has emerged from. The answers to these questions will subsequently reveal the central, unique and peculiar role that comparative constitutionalism has played in the emergence of the EU constitutional narrative. It will be demonstrated and explained how and why a constitutive dependence of the EU constitutional narrative on a very specific comparative constitutional experience actually created two at present major legal and political problems of integration. Finally, by the way of conclusion, the paper will assess why and whether the present EU constitutional narrative, in spite of its numerous drawbacks, should and could be reformed so that the very idea of European constitutionalism could be salvaged and that integration could continue its constitutional journey, albeit following a different track.