Mundaun is a former municipality in the district of Surselva in the canton of Graubünden, Switzerland.

Of the rest of the land, 4.7% is settled (buildings or roads) and the remainder (5.7%) is non-productive (rivers, glaciers or mountains).

[3] The former municipality is located in the Lugnez sub-district of the Surselva district.

It is located on the Obersaxen high plateau south of the Vorderrhein river.

[4] The age distribution, as of 2000[update], in Mundaun is; 43 children or 13.9% of the population are between 0 and 9 years old and 44 teenagers or 14.2% are between 10 and 19.