The Hag of Beara is a mythic Irish Goddess: a Cailleach, or divine hag, crone, or creator deity; literally a "hooded one". She is associated with the Beara Peninsula in County Cork, Ireland, and was thought to bring winter. She is best known as the narrator of the medieval Irish poem "The Lament of the Hag of Beara", in which she bitterly laments the passing of her youth and her decrepit old age. The Great Book of Lecan contains a collection of stories concerning her.

In Gaelic myth, the Cailleach is a divine hag and ancestor, associated with the creation of the landscape and with the weather, especially storms and winter. The word literally means 'old woman, hag', and is found with this meaning in modern Irish and Scottish Gaelic, and has been applied to numerous mythological and folkloric figures in Ireland, Scotland, and the Isle of Man. In modern Irish folklore studies, she is sometimes known as The Hag of Beara, while in Scotland she is known as Beira, Queen of Winter.