Cosme Damián de Churruca y Elorza (born in Motrico, Guipúzcoa, Spain, 27 September 1761; died on Trafalgar Coast, Cádiz, 21 october 1805) was a Spanish noble, a major of Motrico, a military sailor and a scientist.

Educated in Guipúzcoa and Castile, Cosme Damián de Churruca joined the Spanish Navy and performed heroically in a siege of Gibraltar.

He commanded the San Juan Nepomuceno ship in the Battle of Trafalgar, when a cannon ball caused him injuries that cost him his life.