| Nordsee-Treene | |
| Native Name Lang: | de |
| Settlement Type: | Amt |
| Blank Emblem Type: | Logo |
| Subdivision Type: | Country |
| Subdivision Name: | Germany |
| Subdivision Type2: | State |
| Subdivision Name2: | Schleswig-Holstein |
| Subdivision Type3: | District |
| Subdivision Name3: | Nordfriesland |
| Seat Type: | Region seat |
| Seat: | Mildstedt |
| Leader Party: | CDU |
| Leader Title: | Amtsvorsteher |
| Leader Name: | Eva-Maria Kühl |
| Area Total Km2: | 412.1 |
| Population Total: | 23,655 |
| Population As Of: | 2020-12-31 |
| Website: | amt-nordsee-treene.de |
Nordsee-Treene is an Amt ("collective municipality") in the district of Nordfriesland, in Schleswig-Holstein, Germany. Its seat is in Mildstedt. It was formed on 1 January 2008 from the former Ämter Friedrichstadt (except the town Friedrichstadt), Hattstedt, Nordstrand and Treene.
The Amt Nordsee-Treene consists of the following municipalities:
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