Sennwald is a municipality in the Wahlkreis (constituency) of Werdenberg in the canton of St. Gallen in Switzerland.

Of the rest of the land, 9.4% is settled (buildings or roads) and the remainder (9.3%) is non-productive (rivers or lakes).

Of the foreign population, (as of 2000[update]), 79 are from Germany, 65 are from Italy, 391 are from ex-Yugoslavia, 116 are from Austria, 66 are from Turkey, and 103 are from another country.

[7] The age distribution, as of 2000[update], in Sennwald is; 565 children or 12.6% of the population are between 0 and 9 years old and 662 teenagers or 14.8% are between 10 and 19.

[3] Out of the total population in Sennwald, as of 2000[update], the highest education level completed by 1,074 people (24.0% of the population) was Primary, while 1,579 (35.2%) have completed their secondary education, 393 (8.8%) have attended a Tertiary school, and 185 (4.1%) are not in school.

[10] The kybun Corporation of the Swiss engineer Karl Müller produces a part of its shoes in Sennwald.

From the 2000 census[update], 1,355 or 30.2% are Roman Catholic, while 2,176 or 48.5% belonged to the Swiss Reformed Church.