Oberriet is a municipality in the Wahlkreis (constituency) of Rheintal in the canton of St. Gallen in Switzerland.

Of the rest of the land, 12.9% is settled (buildings or roads) and the remainder (4.1%) is non-productive (rivers or lakes).

It also includes the former Imperial palace (Kaiserpfalz) at Kriessern, but not the formerly attached village of Mäder in Vorarlberg and Diepoldsau.

The blazon of the municipal coat of arms is Per fess Or a Lion passant Sable langued and armed of the field and Sable a Cross pattee couped between in chief two Mullets Or.

Of the foreign population, (as of 2000[update]), 54 are from Germany, 63 are from Italy, 461 are from ex-Yugoslavia, 115 are from Austria, 3 are from Turkey, and 88 are from another country.

[8] The age distribution, as of 2000[update], in Oberriet is; 1,043 children or 14.0% of the population are between 0 and 9 years old and 1,017 teenagers or 13.6% are between 10 and 19.

[4] Out of the total population in Oberriet, as of 2000[update], the highest education level completed by 1,778 people (23.9% of the population) was Primary, while 2,742 (36.8%) have completed their secondary education, 554 (7.4%) have attended a Tertiary school, and 329 (4.4%) are not in school.

[11] From the 2000 census[update], 5,920 or 79.4% are Roman Catholic, while 632 or 8.5% belonged to the Swiss Reformed Church.