欧州連合の国境

The border of the European Union consists of the land borders that member states of the EU share with non-EU states adjacent to the union. The EU shares land borders with 21 countries and 3 dependencies.

The lengths of the borders the European Union and the Overseas Countries and Territories (OCTs) share with different countries and territories are listed below. Maritime borders are not included.

The northern part of Cyprus is legally part of the EU, but the terms of the acquis communautaire, the EU's body of laws, have been suspended due to it being under the control of the Turkish Republic of Northern Cyprus, a self-proclaimed de facto state which is recognized only by Turkey. The two entities are separated by the United Nations Buffer Zone in Cyprus, which serves as a de facto boundary between them.

In 2004 the European Union developed the European Neighbourhood Policy (ENP) for the promotion of cooperation between the EU and its neighbours to the east and south of the European territory of the EU (i.e., excluding its outermost regions outside of Europe), which, in part, includes the Cross-Border Cooperation programme aimed at the promotion of economic development in border areas and ensuring border security.

The Border and Coast Guard Agency, more commonly known as Frontex, was established in 2004. Its main task is external border control of the Schengen Area. Most of its activities are coordinated with the coast and border guards of member states.

Should Turkey, which is a candidate for EU membership, accede to the EU, Armenia, Nakhchivan Autonomous Republic, which is part of Azerbaijan, Georgia, Iran, Iraq, and Syria will be a border neighbors with the European Union.