| Château-d'Olonne | |
| Arrondissement: | Les Sables-d'Olonne |
| Canton: | Les Sables-d'Olonne |
| Insee: | 85060 |
| Postal Code: | 85180 |
| Commune: | Les Sables-d'Olonne |
| Coordinates: | 46.505°N -1.7361°W |
| Elevation Min M: | 0 |
| Elevation Max M: | 59 |
| Area Km2: | 31.22 |
| Population: | 14411 |
| Population Date: | 2017 |
| Population Footnotes: | [1] |
Château-d'Olonne (in French pronounced as /ʃɑto dɔlɔn/) is a former commune of the Vendée department in the Pays de la Loire region of Western France. On 1 January 2019, it was merged into the commune of Les Sables-d'Olonne.[2]