| Type: | town |
| County: | Maramureș |
| Official Name: | Seini |
| Leader Name: | Gabriela Florica Tulbure[1] |
| Leader Party: | CMM |
| Leader Term: | 2020 - 2024 |
| Coordinates: | 47.7478°N 23.2853°W |
| Elevation: | 140 |
| Area Total: | 58.91 |
| Population Total: | auto |
| Postal Code: | 435400 |
| Area Code: | (+40) 02 62 |
Seini (German: Leuchtenburg; Hungarian: Szinérváralja) is a town in Maramureș County, Romania. It administers two villages, Săbișa (Kissebespatak) and Viile Apei (Apahegy). It officially became a town in 1989, as a result of the Romanian rural systematization program.
The town is located in the western part of Maramureș County, from the county seat, Baia Mare, on the border with Satu Mare County. It belongs to the Baia Mare metropolitan area.
Seini is crossed by national road (part of European route E58), which runs from Cluj-Napoca north towards Baia Mare and the border crossing at Halmeu, where it connects with the Ukrainian highway M26. The town has two train stations (and Săbișa), both serving the CFR Main Line 400, which connects Brașov with Baia Mare and Satu Mare.
At the 2021 census, Seini had a population of 8,198, of which 77% were Romanians, 12.2% Hungarians, and 2.7% Roma.[2]