Traffic officers did not catch the 25-year-old driver speeding in his bright green Lamborghini Huracan – which can go 0-60mph (97km/h) in 2.5 seconds.
But police said he was driving in an “anti-social manner” and confiscated the Italian supercar.
The driver was given a legal warning which meant the car, which has a top speed of 202mph (325km/h), was seized by police on Wednesday night but handed back the following day.
A spokeswoman for Gwent Police said: “The driver was driving in an anti-social manner – speed not recorded but was excessively speeding in a built-up area.”
The man was warned his car could be seized again if he is caught for a second time.