The Kawahiva tribe, an indigenous people living deep in the Amazon rainforest and have had very little contact with the outside world, were filmed for the first time.
The footage shows the tribe walking through the rainforest. Men are viewed holding bows and arrows while a woman is shown holding a child on her back.
The woman runs away after noticing the camera, and one man briefly doubles back to investigate.
Loggers first reported the existence of the Kawahiva in 1999. A reservation was created last year in the western state of Mato Grosso, but members of the tribe still face grave threats from loggers and farmers.
The video was shot in 2011 by the government’s agency overseeing indigenous matters, but was only released on Wednesday.
According to the Daily Telegraph, a 411,848-acre reservation was set up last year in the western Mato Grosso state.
Carlos Travassos, the head coordinator of the Isolated and Recently Contacted Indigenous groups at FUNAI, said the group faces grave danger.
The Associated Press contributed to this report.