He had heard Rome was expensive, but nothing prepared the Hong Kong tourist for a 990-euro ($1,251) beer.
The unwary visitor received the bill for a drink sipped near Rome's most famous street, Via Veneto, where beers usually cost as much as 10 euros, Rome mayor's office said.
The tourist, who was traveling alone, was invited to the bar by a tout who served him a beer and then said it would cost him 990 euros. He bartered it down to 490 euros, but the bar owner ended up taking 990 euros off his credit card anyway.
"When the bill arrived, I thought it was safer to pay it. I was scared something could happen to me if I didn't," the man, whose name was withheld, told Rome mayor's office, which is investigating the crime.
The tourist, who is from Hong Kong but lives in Germany and has a British passport, tried to report the fraud to the police but said he could not make himself understood because no one spoke English.
Tourists to Rome have surged in the past five years — visitors were up 60 percent in April compared with a year ago — but the unwary can find the Eternal City's charms obscured by the fight to get a fair price.
Most visitors have tales of rip-offs by bar, restaurant and hotel operators, but they often pale beside stories of taxi drivers who can charge hundreds of euros for trips from the airport and then dump those who refuse to pay by the side of the road.