The attack happened Monday afternoon on the Mystic Falls Trail near Old Faithful and Midway Geyser Basin, leading the National Park Service to close nearby trails and backcountry campsites.
Officials said emergency crews responded quickly, but have not identified the bear species, disclosed the hikers' conditions or said whether the pair were together.
It was Yellowstone's first injury-causing bear attack of 2026; attacks are rare in the park, which hosts more than 4 million visitors annually, and the last fatal attack there was in 2015.
What new safety measures might Yellowstone introduce after this spring’s bear attack, and will they be enough to reassure visitors?
How do Yellowstone’s economic and conservation goals intersect when a bear attack leads to major area closures?
Could the push to delist grizzly bears from the Endangered Species Act change how future bear attacks in Yellowstone are handled?