In the footage, people nearby can be heard gasping as the bear charged toward the woman while she was holding up her phone in the Grand Loop Road area earlier this week. The bear suddenly changes course and retreats as the woman quickly walks away.
On its website, the National Park Service says bears use bluff charges to scare and intimidate, adding that visitors should stay at least 100 yards away from them.
Officials say the best way to watch bears is from your car. If they approach you, park visitors are encouraged to honk their car horn and drive away.
WATCH FULL VIDEO: Bear charges toward woman at Yellowstone National Park
Viral video shows cougar stalking Utah hiker in terrifying 6-minute encounter