The lips are free from the gums. The skull is massive, and the tympanic bullae are not inflated. The species Ursus ursinus, however, has only 2 upper incisors and a total of 40 teeth. Ursid incisors are not specialized, the canines are elongate, the first 3 premolars are reduced or lost, and the molars have broad, flat, and tubercular crowns. The carnassials are not developed as such.
Habitats range from arctic ice floes to tropical forests.
Those populations that occur in open areas often dig dens in hillsides. Others shelter in caves, hollow logs, or dense vegetation. Bears have a characteristic shuffling gait. They walk plantigrade, with the heel of the foot touching the ground. They are capable of walking on their hind legs for short distances.