| Ruinas | |
| Official Name: | Comune di Ruinas |
| Native Name: | Arruinas |
| Pushpin Map: | Italy Sardinia |
| Coordinates: | 39.9°N 62°W |
| Region: | Sardinia |
| Province: | Oristano (OR) |
| Mayor: | Ester Tatti |
| Area Total Km2: | 30.46 |
| Population Footnotes: | [1] |
| Population Total: | 669 |
| Population As Of: | 30 November 2015 |
| Population Demonym: | Ruinesi |
| Elevation M: | 365 |
| Postal Code: | 09085 |
| Area Code: | 0783 |
Ruinas (sc|Arruìnas) is a comune (municipality) in the Province of Oristano in the Italian region Sardinia, located about 80km (50miles) north of Cagliari and about 25km (16miles) east of Oristano.
Ruinas borders the following municipalities: Allai, Asuni, Mogorella, Samugheo, Siamanna, Villa Sant'Antonio, Villaurbana.