Tripolitania /trɪpɒlɪˈtniə/ (Arabic: طرابلس Ṭarābulus; Berber: Ṭrables; from Vulgar Latin: *Trapoletanius, from Latin: Regio Tripolitana, from Greek: Τριπολιτάνια) is a historic region and former province of Libya.

طرابلس  (Arabic)
Ṭarābulus  (Arabic)
Τριπολιτάνια  (Ancient Greek)
Ṭrables  (Nafusi)
Tripolitania as a subdivision of Libya 1934–1963.
  Total353,000 km2 (136,000 sq mi)
 (2006)[note 1]
  Density10/km2 (26/sq mi)

The region had been settled since antiquity, first coming to prominence as part of the Carthaginian empire. Following the defeat of Carthage in the Punic Wars, Rome organized the region (along with what is now modern day Tunisia and eastern Algeria), into a province known as Africa, and placed it under the administration of a proconsul. During the Diocletian reforms of the late 3rd century, all of North Africa was placed into the newly created Diocese of Africa, of which Tripolitania was a constituent province.

After the Fall of the Western Roman Empire in the 5th century, Tripolitania changed hands between the Vandals and the Byzantine Empire, until it was taken during the Muslim conquest of the Maghreb in the 8th century. It was part of the region known to the Islamic world as Ifriqiya, whose boundaries roughly mirrored those of the old Roman province of Africa Proconsularis. Though nominally under the suzerainty of the Abbasid Caliphate, local dynasties such as the Aghlabids and later the Fatimid Caliphate were practically independent. The native Berbers, who had inhabited the area locally for centuries before the arrival of the Arabs, established their own native Hafsid dynasty over Ifriqiya in the 13th century, and would control the region until it was conquered by the Ottoman Empire in the 15th century, who established Ottoman Tripolitania as a distinct province.

Tripolitania was a separate Italian colony from 1927 to 1934. From 1934 to 1963, Tripolitania was one of three administrative divisions within Italian Libya and the Kingdom of Libya, alongside Cyrenaica to the east and Fezzan to the south.