Cruise arrived at Rome's small Ciampino airport from Los Angeles with about 10 people, including his mother and his three children, airport officials said.
The 44-year-old actor and Holmes, 27, are set to marry in an undisclosed Italian location Saturday. Speculation on the location has focused on Odescalchi Castle on Lake Bracciano, near the capital. The romantic, 15th-century castle, with its halls and gardens, can host up to 1,400 guests.
Local officials and residents remain tightlipped, and Bracciano's mayor has only acknowledged that authorities received a request to clear the square in front of the castle.
Some 100 fans mingled with photographers and camera crews in front of the Hassler, the luxury Rome hotel on top of the Spanish Steps where Cruise was said by airport officials to be staying. An employee at the hotel's front desk, who refused to give her name, denied that Cruise was staying there.
Traffic police managed the crowd at the Hassler and bodyguards stood at the ready next to limousines parked in front of the hotel.
Holmes and Cruise were engaged in June 2005. Their daughter, Suri, was born April 18.
Cruise has two children, 13-year-old Isabella, and 11-year-old Connor, from his marriage to Nicole Kidman. Kidman and Cruise divorced in 2001 after 10 years of marriage.
Holmes, who starred in TV's "Dawson's Creek," had been engaged to Chris Klein. Cruise was also previously married to Mimi Rogers, and had a high-profile romance with Penelope Cruz.