
State Border of Ukraine is an international boundary of the state territory of Ukraine. According to the Article 1 of the Law of Ukraine on the State Border it is a line and a vertical surface that stretches along that line, which define the boundary of territory of Ukraine over the land, water, and air space.

The Belarusian-Ukrainian border is the state border between Belarus and Ukraine with a length of about 1,084 km (674 mi). It starts from the triple junction with Poland to the west and stretches to the triple junction with Russia to the east. The tripoint border at the triple border junction of Belarus, Russia and Ukraine is marked in the form of a monument, while at the other border junction there is a river, the Western Bug that coincides with the border of Poland.

The modern Moldova–Ukraine border, the official border between Republic of Moldova and Ukraine, was established after the dissolution of the Soviet Union. The length of the inland border is 1,222 kilometres (759 mi), of which 267 kilometres (166 mi), is fluvial and 955 kilometres (593 mi), is land border. About 454 kilometres (282 mi), of it constitutes the de facto border between Ukraine and the unrecognized breakaway republic of Transnistria.
Poland–Ukraine border is the state border between Poland and Ukraine. It has a total length of 535 km (332 mi) or 529 km (329 mi).
The Romania–Ukraine border is the state border between Romania and Ukraine. It consists of land and maritime boundary. The total border length is 613.8 km (381.4 mi) including 292.2 km (181.6 mi) by rivers and 33 km (21 mi) by the Black Sea. It is part of the external border of the European Union.

The Russia–Ukraine border is the international state border between the Russian Federation and Ukraine. Over land the border outlines five oblasts (regions) of Ukraine and five oblasts of the Russian Federation. The modern border issue has been ongoing ever since the fall of the Russian Empire in 1917.

The Slovakia–Ukraine border is an internationally established boundary between Slovakia and Ukraine. Both countries inherited it from their previous respective state organizations, Ukraine from the Soviet Union and Slovakia from Czechoslovakia.

State Border Guard Service of Ukraine or SBGS is the border guard of Ukraine. It is an independent law enforcement agency of special assignment, the head of which is subordinated to the President of Ukraine.