Francisco Pascacio Moreno (May 31 1852 – November 22 1919) was an Argentine explorer, born in Buenos Aires. He is usually referred to as el Perito Moreno (perito means "specialist, expert").

In 1872 Moreno began a series of exploring expeditions that made him well known. In January 1876, he explored Lake Nahuel-Huapi, in the southern Andes, and discovered, on February 14, 1877, Lake San Martin. He also explored numerous rivers in Patagonia, and on 4 March of the same year encountered El Chaltén, which he named Fitz Roy.

In 1880 he went on a second expedition to the territory of Patagonia, where he was taken prisoner by a Pehuelche aboriginal tribe and condemned to death, but escaped on March 11, one day before the one appointed for the execution. In 1882–1883 he explored the Andes from Bolivia southward, and in 1884–1885 he made new explorations of the territory south of the Río Negro and of Patagonia. He was director of the anthropological museum of Buenos Aires, chief of the Argentine exploring commission of the southern territories, and member of numerous European scientific societies.

For his contributions to science, Moreno received a doctorate Honoris causa from the University of Córdoba in 1877. He is also known for his role in defending Argentine interests during the delineation of the international border between Chile and Argentina. In 1902 he was appointed Perito (a technical specialist or expert) in the border conflict.

In 1903 he donated some of the land previously given to him for the creation of the Nahuel Huapi National Park. The Perito Moreno Glacier and the town of Perito Moreno, all in Santa Cruz Province, are named after him.