| Lake Upsilon | |
| Location: | Rolette County, North Dakota |
| Coordinates: | 48.968°N -99.839°W |
| Type: | lake |
| Pushpin Map: | North Dakota |
| Pushpin Map Alt: | Location of the lake in North Dakota. |
Lake Upsilon is a lake in Rolette County, North Dakota, in the United States.
This lake was so named on account of its shape, upsilon meaning Y in Greek.[1]