Ruinas

{{Infobox Italian comune

| name = Ruinas

| official_name = Comune di Ruinas

| native_name = Arruinas

| image_skyline =

| imagesize =

| image_alt =

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| image_shield =

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| image_map =

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| pushpin_map = Italy Sardinia

| coordinates = {{coord|39|54|N|8|54|E|type:city(790)_region:IT|display=inline,title}}

| coordinates_footnotes =

| region = Sardinia

| province = Oristano (OR)

| frazioni =

| mayor_party =

| mayor = Ester Tatti

| area_footnotes =

| area_total_km2 = 30.46

| population_footnotes = All demographics and other statistics: National Institute of Statistics (Italy) (Istat).

| population_total = 669

| population_as_of = 30 November 2015

| pop_density_footnotes =

| population_demonym = Ruinesi

| elevation_footnotes =

| elevation_m = 365

| saint =

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| postal_code = 09085

| area_code = 0783

| website = {{official website|http://www.comune.ruinas.or.it/}}

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}}

Ruinas ({{langx|sc|Arruìnas}}) is a comune (municipality) in the Province of Oristano in the Italian region Sardinia, located about {{convert|80|km|mi}} north of Cagliari and about {{convert|25|km|mi}} east of Oristano.

Ruinas borders the following municipalities: Allai, Asuni, Mogorella, Samugheo, Siamanna, Villa Sant'Antonio, Villaurbana.