Search and rescue teams found only "bodies and more pieces of bodies," said Jose Carlos Pereira, who heads Infraero, the company that manages Brazil's airports.
"There is not the slightest chance of survivors," he told local media.
Rescuers had battled to make their way to the remote crash site, 200 kilometres from the small town of Peixote Azevedo in Mato Grosso state.
The first military teams to reach the ground had to rappel down from helicopters, and then worked on clearing a landing area in the dense forest.
Cause of crash
GOL's flight 1907 crashed after a mid-air collision, Denise Abreu, director of the National Civil Aviation Agency (ANAC), said at a press conference.
GOL Vice President David Birioni said earlier "a Legacy aircraft crashed with our plane."
The Boeing 737 which originated in the northern Amazonian city of Manaus had been bound for Brasilia and then on to Rio de Janeiro.
Authorities were trying to establish whether the airliner had collided with a US-registered Legacy executive jet whose pilot made an emergency landing on Friday in Cachimbo, near the area where the crew of flight 1907 last made contact, 85 minutes into its flight.
Officials indicated the Boeing 737-800 plummeted nose first in the densely forested area of northern Brazil.
The Legacy's "black box" flight recorder has been withdrawn and will be analysed by investigators, Mr Abreu said.
The seven American passengers and crew aboard the Legacy business jet escaped unharmed after the pilot managed to land the damaged plane, which was heading to the United States.
"No one believes we managed to survive a midair collision," said New York Times reporter Joe Sharkey, who was aboard the Legacy, according to the US daily.
He said neither of the smaller plane's two pilots "can understand how a 737 could have hit us without them seeing it."
The GOL airline said a few foreigners were among the passengers, but did not immediately disclose their nationalities. It said four young children and an 11-month-old baby were aboard the ill-fated plane.
President Luiz Inacio Lula da Silva has declared three days of mourning after receiving news of the accident.