Ardenno is a comune (municipality) in the Province of Sondrio in the Italian region Lombardy , located about 90 kilometres (56 mi) northeast of Milan and about 15 kilometres (9 mi) west of Sondrio.

The municipality of Ardenno contains the frazioni (subdivisions, mainly villages and hamlets) Pioda, Biolo, Gaggio, Scheneno, Piazzalunga and Pilasco .

Ardenno borders the following municipalities: Buglio in Monte , Civo , Dazio , Forcola , Talamona , Val Masino .