John Kirwan's side, who face England in their opening RBS 6 Nations clash, looked solid throughout and the Kiwi coach was quick to thank the organisers of the event.
He said: "I would like to thank the Italian Rugby Federation for giving me the chance to play against an excellent team like the World XV.
"We played very well at the start, but as the game wore on we tired because of the all the work we did during the week.
"I'm happy with our attacking play, especially against a top full-back like Brendan Williams of Benetton Treviso."
Italy's try scorers were Andrea Masi, stand-in skipper Andrea De Rossi and Andrea Lo Cicero, with Freddie Tuilagi crossing for the World XV.