|Time zone||UTC + 8 (UTC+8)|
Bayanzürkh (Mongolian: Баянзүрх, lit. "rich heart") is a sum (district) of Khövsgöl aimag (province) in Mongolia. The area is about 4,300 km², of which 2,600 km² are pasture.. In 2000, the sum had 4202 inhabitants, mainly Darkhad. The center, officially named Altraga (Mongolian: Алтрага), is located at the confluence of the Altraga and Beltes rivers, near the Delgermörön river, 127 km northwest of Mörön and 798 kilometers from Ulaanbaatar.
A Bayanzürkh sum was founded, together with the whole aimag, in 1931. In 1933, the bigger part of that sum became Ulaan-Uul sum. In the same year, Bayanzürkh had about 1,100 inhabitants in 499 households, and about 49,000 heads of livestock. Between 1952 and 1990, Bayanzürkh was the seat of the Soyol negdel.
M.Nyamaa, Khövsgöl aimgiin lavlakh toli, Ulaanbaatar 2001, p. 29f