Cudillero (Asturian: Cuideiru) is a municipality in the Principality of Asturias, Spain. Nowadays, Cudillero's main economic activities are related to tourism, but it is also known for its fishing industry. A legend says that it was founded by the Vikings. In addition to Castillian some locals still speak a dialect called Pixueto.

Usually, Spanish-media considers Cudillero as one of the most beautiful villages in Spain.