It is bounded by other communes of Niardo, Bagolino, Bienno, Braone, Ceto, Cividate Camuno, Condino (TN), Daone (TN), Losine, Malegno, Niardo, Prestine.
The town of Breno stands in a north-south gorge, between the castle hill and the Corno Cerreto, on the left bank of the river Oglio.