Preveza (Greek: Πρέβεζα) is a town in the region of Epirus, northwestern Greece, located at the mouth of the Ambracian Gulf. It is the capital of the regional unit of Preveza, which is part of the region of Epirus. The Aktio-Preveza Immersed Tunnel, the first and so far only undersea tunnel in Greece, was completed in 2002 and connects Preveza to Aktio in western Acarnania in the region of Aetolia-Acarnania. The ruins of the ancient city of Nicopolis lie 7 km north of the city.

The name Preveza is of uncertain etymology. There are three versions about the origin of word Πρέβεζα:

The present municipality Preveza was formed at the 2011 local government reform by the merger of the following 3 former municipalities, that became municipal units (constituent communities in brackets):

In antiquity, the area of Preveza was inhabited by the Greek tribe of the Cassopeans, part of larger tribe of the Thesprotians. Their capital city was Cassope (near today's village of Kamarina). Near the site of modern Preveza in 290 BC King Pyrrhus of Epirus founded the town of Berenikea or Berenike, named after his mother-in-law Berenice I of Egypt., Today it is believed that Berenikea lies on the hills of the village of Michalitsi village, following the excavations of Sotirios Dakaris in 1965. The Ambracian Gulf near Berenikea was the site of the Naval Battle of Actium, on 2 September 31 BC, in which Octavian's (later Augustus) forces defeated those of Mark Antony and Queen Cleopatra of Egypt. Ancient Nicopolis (Νικόπολις, "Victory City") was built nearby by Augustus to commemorate his victory, and today it is believed that at its peak it had a total population of 150,000.