| Official Name: | Mellansel |
| Pushpin Map: | Sweden Västernorrland#Sweden#European Union |
| Subdivision Type: | Federation |
| Subdivision Type1: | State |
| Subdivision Type2: | County |
| Subdivision Name2: | Västernorrland County |
| Subdivision Type3: | Municipality |
| Subdivision Name3: | Örnsköldsvik Municipality |
| Area Footnotes: | [1] |
| Area Total Km2: | 2.33 |
| Population As Of: | 31 December 2018 |
| Population Total: | 782 |
| Population Density Km2: | 335 |
| Timezone: | CET |
| Utc Offset: | +1 |
| Timezone Dst: | CEST |
| Utc Offset Dst: | +2 |
| Coordinates: | 63.4333°N 37°W |
Mellansel (pronounced as /sv/)[2] is a locality situated in Örnsköldsvik Municipality, Västernorrland County, Sweden with 827 inhabitants in 2010.
Mellansel was first discovered by humans in 300 BC however Mellansel did not become a permanent settlement until the middle ages. Mellansel was first mentioned in books in the year 1523.[3]
Mellansel became a railway junction when the railway line from Mellansel to Örnsköldsvik was opened to traffic on 1 November 1892. Since the night train traffic has been transferred to the Bothnia Line, no passenger trains have been running through Mellansel station since 2012.
Mellansel Airport (ICAO-code ESUI) is located 4 kilometers south of Mellansel. It opened on 1 July 1973 and no commercial flights operate of it as of 2020.
The largest industry in Mellansel is Bosch Rexroth AB, which manufactures hydraulic drive systems.
There is a college and an outdoor swimming pool in the area. Some of the buildings on the college campus were named after Mellansel's cultural history.
In recent years, Mellansel has become a Population declining area (sv|Avfolkningsbygd).