Château de la Mormaire, Listed castle in Grosrouvre, France.

Château de la Mormaire is a stone castle with symmetrical facades and traditional French roofing in Grosrouvre. The estate sits within an enclosed park that was designed by a landscape architect.

The name Mortuo-Mari appears in 1142 with Milon de Mortuo-Mari and again in 1239 with Nicholaus de Mortua-Mari. Laurent Regnard, counsellor and secretary to King Henri III, acquired the seigneury and had the present château rebuilt; he later added the fiefs of La Mandreux in 1606 and La Noue in 1612. The château and its park, redesigned at the end of the 20th century, were inscribed as monuments historiques on 17 December 1990.

The name derives from Old French mortum, "stagnant", and mare, "sea", meaning "the place by the great stagnant marsh". Written forms changed over time: Milon de Mortuo-Mari in 1142, Mormère in 1635, Morte-mer in 1703, La Mormaire around 1850. The etymology is linked to that of Mortemer Abbey in the Oise.

The château and its park were inscribed as monuments historiques on 17 December 1990, covering both the 17th-century building and the park redesigned at the end of the 20th century. The property is privately owned, so access to the interior and grounds is not open by right; arrange any visit in advance with the owner.

The 1990 heritage listing covers both the 17th-century château and the park, which was redesigned in the late 20th century. Earlier owners include press magnate Hippolyte Auguste Marinoni and financier Robert Cottin, son-in-law of minister Maurice Richard.