The bison was walking near a boardwalk at Black Sand Basin, just north of Old Faithful, when the woman approached it on Monday, according to a park statement. She got within 10 feet before the animal gored her and tossed her 10 feet into the air.
The woman from Grove City, Ohio, sustained a puncture wound and other injuries.
Park emergency medical providers responded and transported her via ambulance to a hospital in Idaho.
Park officials say it’s the first reported bison goring this year. The park statement said bison are unpredictable, have injured more people in Yellowstone than any other animal, and can run three times faster than humans.
Park regulations require visitors to remain more than 25 yards away from bison. The park statement said two other people were also within 25 yards of the same bison.
The incident was under investigation. No additional information was immediately available.