Italian submarine Enrico Toti (S 506) was the first of a new class of Italian submarine (Toti class), with Enrico Toti being laid down in 1965, launched in 1967, decommissioned in 1992 and preserved as a museum ship at thea Museo della Scienza e della Tecnologia "Leonardo da Vinci", in Milan.

The ship, and class, are named after the Italian war hero Enrico Toti.

They had two main tasks: Enrico Toti arrived at the Museo della Scienza e della Tecnologia "Leonardo da Vinci" in August 2005 with a trip in two steps: As museum ship Enrico Toti is unusual, because Milan has no direct access to the sea or a significant river.

The transportation of the sub to the museum was made overnight in mid-August, to minimize inconvenience to the population.

Another Toti-class unit is on exhibition at the Arsenale in Venice, while the remaining two are scheduled for scrapping.