This paper presents the understanding of the constitutional identity in the jurisprudence of the Polish Constitutional Court, with regard to European integration. The Court defines constitutional identity as a sum of certain legal principles of the Constitution of 1997. It seems more adequate to understand identity as allowing changes, including amendments of the core provisions of the Constitution, which do not destroy constitutional identity. This is named limited, or narrative constitutional identity. Constitutional identity is an indicator for the issue of constitutional change. The Constitution of 1997 has quite profoundly changed, although no formal amendment took place. Still the Constitution has maintained its identity. The awareness of constitutional identity can complicate the discussion of constitutional change, specifically the possibility to change the Constitution at any time. The Constitution of 1997 contains a safeguard against its changes, constitutional identity.