| Bayanbulag District | |
| Native Name: | Mongolian: Баянбулаг сум |
| Native Name Lang: | mn |
| Settlement Type: | District |
| Pushpin Map: | Mongolia |
| Pushpin Label Position: | right |
| Pushpin Map Caption: | Location in Mongolia |
| Subdivision Type: | Country |
| Subdivision Name: | Mongolia |
| Subdivision Type1: | Province |
| Subdivision Name1: | Bayankhongor |
| Unit Pref: | Imperial |
| Area Total Km2: | 3,170 |
| Timezone: | UTC+8 |
| Coordinates: | 46.8081°N 98.0911°W |
Bayanbulag (Mongolian: Баянбулаг, rich spring) is a sum (district) of Bayankhongor Province in southern Mongolia. In 2006, its population was 2,143.[1]
Bayanbulag has a cold semi-arid climate (Köppen climate classification BSk) with mild summers and severely cold winters. The climate is very dry; most precipitation falls in the summer as rain, with some snow in the adjacent months of May and September. Winters are very dry.