| Napanee River | |
| Pushpin Map: | Canada Southern Ontario |
| Pushpin Map Caption: | Location of the mouth of the Napanee River in southern Ontario |
| Subdivision Type1: | Country |
| Subdivision Name1: | Canada |
| Subdivision Type2: | Province |
| Subdivision Name2: | Ontario |
| Subdivision Type3: | Region |
| Subdivision Name3: | Eastern Ontario |
| Subdivision Type4: | Counties |
| Source1: | Camden Lake |
| Source1 Location: | Stone Mills, Lennox and Addington County |
| Source1 Coordinates: | 44.4428°N -76.8478°W |
| Source1 Elevation: | 146m (479feet) |
| Mouth: | Lake Ontario |
| Mouth Location: | Greater Napanee, Lennox and Addington County |
| Mouth Coordinates: | 44.1956°N -77.0219°W |
| Mouth Elevation: | 74m (243feet) |
| River System: | Great Lakes Basin |
| Tributaries Left: | Depot Creek |
The Napanee River is a river in Lennox and Addington County and Frontenac County in Eastern Ontario, Canada.[1] It is in the Great Lakes Basin and flows from its source at Camden Lake to its mouth at the Bay of Quinte on Lake Ontario at Napanee. It flows through a valley of preglacial origin. The valley of the Napanee is lined with settlements such as Greater Napanee, Newburgh, Camden East, Yarker, and Petworth.
This river was originally called the Appanea.[2] A grist mill was constructed on the river in 1785 near the current site of the town of Greater Napanee. Other mills were added at Yarker and Camden East.