The 23-year-old singer had his arm draped around the girl's shoulder after stepping out from a party at the Hotel Fosano in Rio De Janeiro, reported HollywoodLife.
The mystery woman was reported to be Luciana Chamone, who was also invited to the party where she joined her friend Marina Pumar.
The group then headed back to the singer's rented mansion to continue the celebrations.
On the following day, Biber was spotted FaceTiming the same girl after hiking through the Rio Rainforest. He was all smile as he held his phone out of the car, revealing her face to his fans.