| Arosio | |
| Official Name: | Comune di Arosio |
| Coordinates: | 45.7167°N 22°W |
| Region: | Lombardy |
| Province: | Province of Como (CO) |
| Area Total Km2: | 2.7 |
| Population Total: | 4521 |
| Population As Of: | Dec. 2004 |
| Population Demonym: | Arosiani |
| Elevation M: | 300 |
| Saint: | SS. Nazario e Celso |
| Day: | 28 July |
| Postal Code: | 22060 |
| Area Code: | 031 |
Arosio (Brianzöö: Aroeus; locally Roeus) is a comune (municipality) in the Province of Como in the Italian region Lombardy, located about 30km (20miles) north of Milan and about 15km (09miles) southeast of Como. As of 31 December 2004, it had a population of 4,521 and an area of 2.7km2.[1]
Arosio borders the following municipalities: Carugo, Giussano, Inverigo.
Arosio is a valuable town in Brianza a geographical area at the foot of the Alps, and is a part of the Parco della Valle del Lambro.It is crossed by two important roads named Nuova Vallassina and Novedratese
The town hosted the Institute for Invalids where Don Carlo Gnocchi founded the Federation for Mutilated Children, in 1952 began the Juvenile Foundation, today known as the Don Carlo Gnocchi – ONLUS Foundation.
The bird observatory Osservatorio Ornitologico di Arosio was established in 1710. It has a museum.