Benjamin Cloutier was killed Sunday while cleaning the bears' enclosure at Animals of Montana in Bozeman, ABC News reported Monday.
"He was a highly experienced trainer, and it is unlikely that the bears caused his death," said Demetri Price, Animals of Montana's lead head trainer. "He had the right safety equipment and the right training to avoid that kind of attack."
Price said Cloutier, who had been with the company since 2008, might have slipped in the cage or hit his head before he was mauled.
One of the three bears in the enclosure had to be killed so Cloutier's body could be recovered.
The company provides wild animals that have been bred in captivity for photo shoots and motion pictures.
Cloutier's cause of death is pending an autopsy.
The Gallatin County coroner and wardens from Montana Fish, Wildlife and Parks are investigating the death.