| Lönkytin | |
| Map: | Finland |
| Coordinates: | 65.2392°N 29.05°W |
| Waterbody: | Bay of Bothnia |
| Country: | Finland |
| Country Admin Divisions Title: | Region |
| Country Admin Divisions: | Northern Ostrobothnia |
| Country Admin Divisions Title 1: | Subregion |
| Country Admin Divisions 1: | Oulu |
| Country Admin Divisions Title 2: | Municipality |
| Country Admin Divisions 2: | Oulu |
| Population: | Uninhabited |
Lönkytin is an island in the Finnish sector of the Bay of Bothnia, off shore from the town of Haukipudas.
Lönkytin is a high, rocky islet. It is located about west-northwest of the mouth of the Kiiminkijoki river, to the east of the Oulu and Kemi deep-water route.The island has a radar reflector.[1] It is near one of the deepest parts of the Finnish sector of the Gulf of Bothnia, at some places reaching a depth of .[2]
The second-closest island to the east is Satakarinletto.