| Melvin River | |
| Pushpin Map: | New Hampshire#USA |
| Pushpin Map Size: | 250 px |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | New Hampshire |
| Subdivision Type3: | County |
| Subdivision Name3: | Carroll |
| Subdivision Type4: | Town |
| Subdivision Name4: | Tuftonboro |
| Length: | 8.1miles |
| Source1: | Melvin Pond |
| Source1 Location: | Tuftonboro |
| Source1 Coordinates: | 43.7094°N -71.2158°W |
| Source1 Elevation: | 750feet |
| Mouth: | Lake Winnipesaukee |
| Mouth Location: | Melvin Village |
| Mouth Coordinates: | 43.6875°N -71.3053°W |
| Mouth Elevation: | 504feet |
The Melvin River is an 8.1adj=midNaNadj=mid[1] river in the Lakes Region of central New Hampshire in the United States. It is a tributary of Lake Winnipesaukee, part of the Merrimack River watershed.
The Melvin River lies entirely within the town of Tuftonboro. It begins at the outlet of Melvin Pond, near the town's eastern border, and flows west along the base of the Ossipee Mountains to the north. The river reaches Lake Winnipesaukee at Melvin Village.