| Onzo | |
| Official Name: | Comune di Onzo |
| Coordinates: | 44.0667°N 11°W |
| Region: | Liguria |
| Province: | Savona (SV) |
| Frazioni: | Varavo Superiore, Varavo Inferiore, Ponterotto, Menezzo, Costa, Capitolo |
| Mayor: | Alessandro Bottello |
| Area Total Km2: | 8.23 |
| Population Footnotes: | [1] |
| Population Total: | 216 |
| Population As Of: | 31 December 217 |
| Population Demonym: | Onzesi |
| Elevation M: | 410 |
| Postal Code: | 17030 |
| Area Code: | 0182 |
Onzo (Onsu) is a comune (municipality) in the Province of Savona in the Italian region Liguria, located about 80km (50miles) southwest of Genoa and about 45km (28miles) southwest of Savona.
Onzo borders the following municipalities: Aquila di Arroscia, Casanova Lerrone, Castelbianco, Nasino, Ortovero, Ranzo, and Vendone.