Cerdanya (Catalan pronunciation: [səɾˈðaɲə]; Spanish: Baja Cerdaña, pronounced [ˈbaxa θeɾˈðaɲa]; French: Basse-Cerdagne, pronounced [bɑs sɛʁdaɲ, bas-]) is a comarca in northern Catalonia, in the Pyrenees, on the border of Catalonia with France and Andorra.

Cerdanya's neighbouring comarques are Alt Urgell, Berguedà, and Ripollès.

Cerdanya is in the "vegueria" of Alt Pirineu, according to "Vegueries of Catalonia law".

"Subcomarques" include la Batllia or petita Cerdanya, and el Baridà.

Llívia is a Catalan exclave in Cerdanya, completely surrounded by French territory.