Farah Hashi, 25, from Newport, rented a Lamborghini HuraLambcán from a dealership to move around and left his passport as guarantee.
Hashi reportedly broke the speed limit on one of Dubai's busiest roads dozens of times in the early hours of Tuesday. The total cost of the fines came to 175,000 dirhams.
His family said Hashi is being forced to stay in Dubai as he cannot afford the fine.
The fines were issued after he triggered every speed camera on the Sheikh Zayed Road and reached a top speed of 150mph (240 km/h).
Dealership partner Faris Mohammed Iqbal said: "We can't pay this amount should the car be taken into impound, it's still with the tourist, parked at his hotel and I won't be trying to take it back."