| Bayandelger District | |
| Native Name: | Баяндэлгэр сум |
| Native Name Lang: | mn |
| Settlement Type: | District |
| Pushpin Map: | Mongolia |
| Pushpin Label Position: | left |
| Pushpin Map Caption: | Location in Mongolia |
| Subdivision Type: | Country |
| Subdivision Name: | Mongolia |
| Population As Of: | 2009 |
| Population Total: | 4,569 |
| Utc Offset: | +8 |
| Coordinates: | 45.7275°N 112.3569°W |
| Elevation Footnotes: | [1] |
| Elevation M: | 1110 |
| Elevation Ft: | 3645 |
Bayandelger (Mongolian: Баяндэлгэр, Rich expanse) is a sum (district) of Sükhbaatar Province in eastern Mongolia. The population (as of 2009) of the sum is 4,569, including 1,169 in the sum center.[2]
Bayandelger has a cold semi-arid climate (Köppen climate classification BSk) with warm summers and very cold winters. Most precipitation falls in the summer as rain. Winters are very dry.