The contract is worth more than €260m ($285.2m), of which the EU bank will provide €205m ($224.8m).
These five-car trains will replace the old vehicles that serve lines 1 and 3 of the metro network.
Alstom will be responsible for the design, manufacturing and commissioning of the trains.
All train cars will be manufactured at Alstom’s Spanish site in Barcelona and are scheduled for delivery in two and a half years.
Alstom Europe senior vice-president Gian Luca Erbacci said: “The expertise and innovation capabilities of our teams are fully mobilised to support the plan to modernise Barcelona Metro for the benefit of passengers.
“Carrying over 400 million passengers per year, the Barcelona network is one of the most efficient and modern in Europe. With our trains, we aim to help TMB in the development of efficient and sustainable mobility that responds to the current and future needs of all passengers.”
The new Metropolis trains will adhere to sustainability criteria, such as light structure, high levels of recoverability and recyclability, low energy consumption, technical reliability and ease of maintenance.
The trains will also feature remote sensors to ensure optimal maintenance.
TMB president Rosa Alarcón said: “With the withdrawal of the oldest fleet, we accelerate a process of renovation that will increase service reliability, sustainability and passenger comfort in two of our most frequented Metro lines, in a context of maximum demand for the collective transport of Barcelona, upon the entry into force of the low-emission zone.”
Metropolis trains are currently serving on line 9 and 10 of the metro network.
In June, Alstom received a contract from Barcelona Metro operator TMB to develop a train driving simulator for Barcelona Metro’s line 9 and 10.
In May 2018, the Singapore Land Transport Authority (LTA) signed an agreement to procure 17 additional Metropolis trains.