Mungialdea is a comarca of the province of Biscay, in the Basque Country, Spain. Mungialdea is the heir of the historical region of Uribe, which was one of the merindades of Biscay. It comprises the most rural area of the historical region of Uribe, drained by the river Butron and with some small municipalities. It is one of the seven comarcas that compose the province of Biscay. Its capital city is Mungia.