The Horned Coot (Fulica cornuta) is a species of bird in the Rallidae family. It is found in Argentina, Bolivia, and Chile.

This species of coot was first collected from the highlands of Bolivia in 1853 and described by Bonaparte and it was known for long by just the specimen and little was known of its life history. It is found in high cordillera of Peru, Bolivia and extreme north of Chile between Caritaya lake and the head of the Huasco river (Atacama) and is not found below 3000 m altitude. The Giant Coot is allopatric with this species and is found north of the distribution range and this species reaches almost the same size, measuring 19 to 20 inches in length.

While most coots have a horny shield on the forehead, the Horned Coot has three wattles in both sexes. The central wattle is large and may possibly be erectile. The three wattles terminate in tufts of filoplumes. At the base of the beak and below the wattle is a fleshy caruncle which is whitish. The bill is olive yellow, brightening to dull orange towards the base.

Lake with two nests in the water close to the shoreline

The nest of the Horned Coot is unique and is located 40 metres from the shore in the waters of the high altitude lakes where it breeds. Pebbles are piled by the birds to form an artificial island that reaches the water surface. This island is then covered with algae to form the nest. It has been estimated that the pebble mounds may weigh as much as 1.5 tons and they are refurbished in each season. They breed in winter from November to January.

Its natural habitats are freshwater lakes and saline marshes. It is threatened by habitat loss.