Bidders are invited to submit offers by October 29 and the scoring criteria will be weighted in favour of the best economic offer, although ANM qualitative aspects and delivery time will also be key considerations in the competition.
The standard-gauge trains will supplement the Firema/Ansaldo/Breda trains already in service on Line 1, which opened in 1993.
The Naples' Councillor for Transport Mr Mario Calabrese said that passengers on Line 1 will benefit from greater comfort, increased frequency, and better quality services as a result of this investment.
Line 1 is currently being extended from Garibaldi station to Naples International Airport at Capodichino and the tender includes options for additional trains to support future phases of the line.
At present Line 1 carries around 135,000 passengers per day on weekdays, with services running at eight minute headways at peak times.