The new Alitalia measure is already in place and applies to all its flights, a spokesman for the airline told The Local on Friday.
The decision to have two people in the cockpit at all times follows the announcement on Thursday that a co-pilot deliberately caused a plane crash in which all 150 people on board died.
Andreas Lubitz was named by investigators as being solely responsible for the Germanwings disaster in the French Alps, after locking the pilot out of the cockpit and forcing the plane to crash.
As a result a number of airlines have changed their rules, to make sure a second member of the flight crew is present when one of the pilots steps out of the cockpit.
British carrier easyJet announced the change on Thursday, while airlines Icelandair and Norwegian Air Shuttle were among those to implement the two-person cockpit rule.