Réserve naturelle nationale de Moëze-Oléron, National nature reserve in Charente-Maritime, France.

The Réserve naturelle nationale de Moëze-Oléron is a protected natural area at the mouth of the Charente River, consisting of extensive marshes, tidal flats, and water zones. The terrain is shaped by tidal movements that daily reshape the landscape, creating a complex mosaic of water, reeds, and muddy expanses.

The area took shape between 1830 and 1850 through the creation of polders that modified the salt marshes and wetlands. Official protection status was established in 1985 to preserve the valuable ecosystems and migratory birds.

The name joins Moëze, the mainland commune, and Oléron, the island closing the reserve to the west. The Maison de la réserve at the Ferme de Plaisance, in Saint-Froult, receives visitors, and four discovery trails run around the reserve's edge, one of them labelled for disabled access.

Only two trails give access to a minor part of the reserve; the rest, including three integral reserves created in June 2012, is closed except to a few professional rights-holders. The reception and information point is the Ferme de Plaisance, in the south-east on the commune of Saint-Froult, with four discovery trails around the reserve, one partly labelled for nature and disability access.

The reserve is one of France's five most important wintering sites for water birds and attracts tens of thousands of migratory birds each year. This international richness of bird species makes it an ecologically significant place, even though it remains less well known than other French protected areas.