The Naples Metro (Italian: Metropolitana di Napoli) is a rapid transit system serving the city of Naples, Campania, Italy and some parts of the adjacent comuni of its metropolitan area through Line 11. The system comprises three underground rapid transit lines (Line 1, Line 6 and Line 11).

It is the third largest underground network in Italy, behind Milan and Rome.

The Metro comprises three lines – 1 (yellow), 6 (blue) and 11 (rainbow or orange) – which operate on 34.5 km (21.4 mi) of route, serving 30 stations. It has a daily ridership of approximately 115,000 passengers, and an annual traffic of approximately 45 million passengers.

In addition to the Metro, the central area of Naples and its surrounding urban region are served by eight railways forming the Naples metropolitan railway service. These include six Circumvesuviana lines, spanning 142.7 kilometres (88.7 mi) and comprising 96 stations; Line 2, extending 18.9 kilometres (11.7 mi) with 12 stations; the Cumana railway, covering 19.81 kilometres (12.31 mi) with 14 stations; and the Circumflegrea railway, which stretches for 27.04 kilometres (16.80 mi) and includes 16 stations. Together, these railway networks provide extensive connectivity across Naples and the wider Campania region.

In 1911, construction on the urban section of the Rome–Formia–Naples railway, the Villa Literno–Napoli Gianturco railway was commenced, and although it was suspended for the duration of World War I, the line was eventually opened on 28 September 1925 as an urban railway service line, the first in Italy. This service is now known as Line 2.

After World War II, the existing Circumvesuviana railway was upgraded to a modern commuter rail, and also the Cumana railway became relevant for the commuter transport. In 1962, the Circumflegrea railway was opened.

Construction of the first underground metro railway (Line 1) began in 1976, and the first part opened on 28 March 1993. Initially called the Metropolitana Collinare ("Hills metro") it ran for 4 km (2.5 mi) between Colli Aminei and Vanvitelli. Two years later, in 1995, the line was extended to reach Piscinola giving an overall track length of 8 kilometres (5.0 mi).

Although progress had been made from the early setbacks and problems, it was still apparent by 1997 that the network suffered badly from the lack of network integration and poor connections, as well as the fact that large areas of Naples were not close to stations. In 1997, the city government drew up a new Piano Comunale dei Trasporti di Napoli (City Transport Plan) which called for a review of the network, improved controls over maintenance expenditure and general finances, a new tariff control system and better management of the urban rail network of Naples.