The 29-year-old was booked into the Clark County Detention Center early Saturday and released on her own recognizance a few hours later, Las Vegas police spokesman Marcus Martin told the AP.
Hilton was in a car driven by a friend when it was stopped late Friday after police officers detected what they thought to be marijuana smoke coming from the vehicle, Martin said.
During the stop, police found a substance on Hilton that later tests showed to be cocaine, Martin said. It is unknown how much was found.
The person driving the car was arrested on charges of driving under the influence of drugs.
"Paris Hilton was released this morning on her own recognizance. This matter will be dealt with in the courts, not in the media, and I encourage people not to rush to judgment until all of the facts have been dealt with in a court of law," her attorney, David Chesnoff, said in a statement. "There will be no interviews and no more comments at this time."
Earlier this week, Nathan Lee Parada was charged with attempted burglary on suspicion of breaking into Hilton's Los Angeles home.
In July, she was arrested on suspicion of possession of marijuana at the World Cup in South Africa. The charge was later dropped.