There are 2 types of trains in service on the line. The first type is the ET245, which was introduced in 1969 with the opening of the line and was the first train operated on Line 2. ET245 are formed by three-car consists, with Bo-Bo powered units at both ends and a car between them; normally, two consists are coupled to form a single train. This series came in two different versions for urban and suburban routes. The first had 8 doors per car and regular seats, while the latter was equipped with only 6 doors per car and more seats. Original ET245 trains are still in service on the line. Of these, some have been renewed in latest years. The second type in operation is the new
AnsaldoBreda Meneghino train. The first train was introduced in April 2009. In 2015, the followed, with the two newer series jointly replacing all the other stock, which is due to be retired by 2020. Originally, as its own trains were not ready yet, Line 2 provisionally operated with 100/200 Series trains transferred from Line 1. As the 300/400 Series trains were delivered starting from 1970, the 100/200 Series trains were moved back to line 1. The three-doors 300/400 Series trains were manufactured between 1970 and 1981, and in 1985 the 350 Series was introduced, which was an improved version of the earlier 300 Series with four doors instead of three. 350 Series trains were produced in 2 batches between 1985 and 1991. In 1987 the 500 Series was introduced, consisting of three experimental trains designed to test the new
GTO–
VVVF inverters that were to equip Line 3's 8000 Series. ==Planned extensions==