| Châteaulin | |
| Commune Status: | Subprefecture and commune |
| Image Coat Of Arms: | Blason ville fr Châteaulin (Finistère).svg |
| Coordinates: | 48.1975°N -4.0886°W |
| Insee: | 29026 |
| Postal Code: | 29150 |
| Arrondissement: | Châteaulin |
| Canton: | Crozon |
| Mayor: | Gaëlle Nicolas[1] |
| Term: | 2020 - 2026 |
| Intercommunality: | Pleyben-Châteaulin-Porzay |
| Elevation Min M: | 2 |
| Elevation Max M: | 206 |
| Area Km2: | 20.81 |
Châteaulin (in French ʃɑtolɛ̃/; Breton: Kastellin) is a commune in the Finistère department and administrative region of Brittany in north-western France. It is a sub-prefecture of the department.
Châteaulin is in a valley towards the center of Finistère on the River Aulne and the Canal de Nantes à Brest, mid-way between Quimper to the south and Brest to the north. To the west the Menez-Hom hills separate it from the Crozon peninsula and the Bay of Douarnenez, which opens into the Atlantic Ocean.
In French the inhabitants of Châteaulin are known as Châteaulinois.
In 2008 1.96% of primary-school children attended bilingual schools.[2]
Châteaulin's economy is based on food processing (salmon and poultry) and, to an ever-greater extent, tourism. The Gendarmerie school on the outskirts of the town provides for a large number of families and the many recruits passing through the school provide the economic backbone of the town's night-life.The cake shop Histoire de Macaron is famous for its tasty and wide range of macaroons as well as the Java, created in 1907 by Mister Le Meur, which is a legend in the town.
Châteaulin is twinned with: