| Tämnarån | |
| Subdivision Type1: | Country |
| Subdivision Name1: | Sweden |
| Subdivision Type3: | County |
| Length: | 99km (62miles) |
| Mouth: | Bothnian Sea |
| Mouth Location: | Karlholmsbruk, Tierp Municipality |
| Mouth Coordinates: | 60.5239°N 17.6486°W |
| Mouth Elevation: | 0m (00feet) |
| Basin Size: | 1258.1km2[1] |
Tämnarån is an approximately 60 km long river in the northern parts of the Swedish historical province Uppland.