In this article we argue that the EU suffers from autoimmunity: a self-harming protection strategy. Drawing on Derrida's political understanding of autoimmunity, we contend that the root of this malfunction lies in the EU's own b/ordering and othering policies, which are intended to immunise the foundational ethos of the EU. For this purpose, we dissect the EU border regime into three linked b/ordering mechanisms: the pre-borders of paper documents that regulate from afar the mobility of the people from visa-obliged countries; the actual land borders often consisting of iron gates and fences regulating mobility on the spot; and the post-border in the form of waiting/detention camps that segregate and enclose the undocumented migrants after entry. We make clear how this discriminatory b/ordering and othering regime has led to a recurrent drawing of ever less porous, inhumane and deadlier borders. Such thanatopolitics finds itself at odds with the humanist values that the EU is supposed to uphold, particularly cross-border solidarity, openness, non-discrimination and human rights. We argue that the EU b/ordering regime has turned fear of the non-EUropean into an increasingly unquestionedeven 'commonsensical'anxiety that has become politically profitable to exploit by extreme nationalistic and EUrosceptic parties. The core of the EU's autoimmunity that we want to expose lies within this irony: in its attempt to protect what it considers meaningful, the EU has unleashed an autoimmune disorder that has turned the EU into its own most formidable threat.DRAWING INSPIRATION from the cultural, religious and humanist inheritance of Europe, from which have developed the universal values of the inviolable and inalienable rights of the human person, freedom, democracy, equality and the rule of law.-Lisbon Treaty