Bayandelger (Mongolian: Баяндэлгэр, Rich wide) is a sum in the west of Mongolia's Töv Province.

[1] The sum was founded in 1923, under the name Gün sum and as part of the khoshuu of Darkhan Khoshoi Chin Wang Puntsogtsereng[2] in the Tüsheet Khan aimag.

In 1956 it was split between the Bayan and Erdene sums, with most of the territory going to the latter.

[4] D. Natsagdorj was born in what is now Bayandelger sum.

This Mongolia location article is a stub.