Butrint (Greek: Βουθρωτόν and Βουθρωτός, romanized: Bouthrōtón, Latin: Buthrōtum, Albanian: Butrint) was an ancient Greek polis and later Roman city and the seat of an early Christian bishopric in Epirus.

Originally a settlement of the Greek tribe of the Chaonians, it later became part of the state of Epirus and later a Roman colonia and a Byzantine bishopric. It entered into decline in Late Antiquity, before being abandoned during the Middle Ages after a major earthquake flooded most of the city. In modern times it is an archeological site in Vlorë County, Albania, some 14 kilometres (8.7 mi) south of Sarandë, close to the Greek border. It is located on a hill overlooking the Vivari Channel and is part of the Butrint National Park. Today, Bouthrotum is a Latin Catholic titular see and also features the Ali Pasha Castle.

The city is considered one of the most important archaeological sites in Albania. On the strength of the immense wealth of cultural, historical and natural value with a considerable history, Butrint was declared a UNESCO World Heritage Site in 1992 and further a National Park in 2000 under the leadership of Auron Tare, its first director.

The earliest archaeological evidence of settled occupation dates to between 10th and 8th centuries BC, although some claim that there is earlier evidence of habitation dating from the 12th century BC.^{[need quotation to verify]}

Excavation at Bouthroton has yielded Proto-Corinthian pottery of the 7th century and then Corinthian and Attic pottery of the 6th century, however there are no indications of a prehistoric settlement. Bouthroton was in a strategically important position due its access to the Straits of Corfu, and its location at the crossroads of mainland Greece and Magna Graecia, the Greek and the "barbarian" worlds. Thus, it became one of the two ancient ports in lower Chaonia, the other being Onchesmos (modern Sarandë).

Bouthroton (modern day Butrint) was originally one of the major centres of the Epirote tribe of the Chaonians, part of the northwestern Greek group of tribes. They had close contacts to the Corinthian colony of Corcyra (modern Corfu). According to the Roman writer Virgil, its legendary founder was the seer Helenus, a son of king Priam of Troy, who had moved West after the fall of Troy with Neoptolemus and his concubine Andromache. Both Virgil and the Greek historian Dionysius of Halicarnassus recorded that Aeneas visited Bouthroton after his own escape from the destruction of Troy.

The acropolis was erected on a hill on the bank of a lake Butrint (or lake Bouthrotum). The first extension of the 7th century BC acropolis occurred during the 5th century BC. During the first years of the second Peloponnesian War (413–404 BC) the Corkyreans built fortifications stretching from Ksamil to Buthrotum. Buthrotum being previously an independent city, became subject to nearby Corfu.

By the 4th century BC it had grown in importance and included a theatre, a sanctuary dedicated to Asclepius and an agora. The acropolis of Bouthrotum was protected by three circuit walls. The last and outer wall was erected around 380 BC enclosing and area of 4ha. This 870m-long wall included bastions and five gates. Two of the most important gates were known as Scean and Lion gate. Moreover, the agora, the stoas, the residential zone and the theatre were located in a separate walled area.