| Buttermilk Creek | |
| Pushpin Map: | Canada Southern Ontario |
| Pushpin Map Caption: | Location of the mouth of Buttermilk Creek in southern Ontario |
| Subdivision Type1: | Country |
| Subdivision Name1: | Canada |
| Subdivision Type2: | Province |
| Subdivision Name2: | Ontario |
| Subdivision Type3: | Region |
| Subdivision Name3: | Eastern Ontario |
| Subdivision Type4: | County |
| Subdivision Name4: | Renfrew |
| Subdivision Type5: | Township |
| Subdivision Name5: | Whitewater Region |
| Length: | 3.9km (02.4miles) |
| Source1: | Astrolabe Lake |
| Source1 Coordinates: | 45.6053°N -76.8381°W |
| Source1 Elevation: | 148m (486feet) |
| Mouth: | Muskrat River |
| Mouth Coordinates: | 45.6236°N -76.8694°W |
| Mouth Elevation: | 126m (413feet) |
| River System: | Saint Lawrence River drainage basin |
Buttermilk Creek is a tributary of the Muskrat River in the township of Whitewater Region, Renfrew County, Ontario, Canada.
Buttermilk Creek begins at Astrolabe Lake, formerly Green Lake and within the grounds of Logos Land water park, and travels 3.9km (02.4miles) before reaching its mouth at the Muskrat River near the community of Cobden. The Muskrat River empties into the Ottawa River at Pembroke.
Ontario Highway 17 parallels the lower ⅔ of the creek. Buttermilk Creek Trout Farm, in operation raising rainbow trout for more than 20 years, is located on the creek banks.