The team, which has taken over the branding of Sauber's 2018 entry, is using one of its two allowed promotional events to run the car ahead of pre-season testing next week.
These first images from Fiorano reveal Kimi Raikkonen behind the wheel of the Alfa, which has appeared in a black-and-red camouflage livery.
The livery incorporates hearts, as the car has appeared on Valentine's Day, and Alfa's Quadrifoglio shamrock that it uses to identify its high-performance models.
Alfa's new F1 car has not yet been named. It is due to be unveiled officially next Monday, before testing begins at Barcelona.