The pic du Grand Quayrat is a French pyrenean summit, culminating at in the vallée d'Oô (commune d'Oô near Bagnères-de-Luchon in the Haute-Garonne department, Midi-Pyrénées region).
Its name in Occitan , meaning "square", comes from the distinctive shape of the summit, roughly forming a right angle, from the north.
The Grand Quayrat became the second climbed three thousander in 1789, ascended by physician Henri Reboul, leading an expedition from the barnes of Astau.