The Nazca Booby, Sula granti, is a booby which is found in the eastern Pacific Ocean, namely on the Galápagos Islands where it can be seen by eco-tourists, and on Clipperton Island. The Revillagigedo Islands off Baja California which possibly constitute its northeasternmost limit of its breeding range.

It was formerly regarded as a subspecies of the Masked Booby but the Nazca Booby is now recognized as a separate species. They differ in regard to ecological and morphological as well as mtDNA cytochrome b sequence data. The Nazca Booby co-occurs with the Masked Booby on Clipperton Island, where they may rarely hybridize.

Nazca boobies are known for practicing habitual siblicide. They lay two eggs, several days apart. If both eggs hatch, the elder chick will push its sibling out of the nest area, leaving it to die of thirst or cold. The parent booby will not intervene and the younger chick will inevitably die. It is believed that two eggs are laid so that one remains an insurance in case the other gets destroyed or eaten e.g. by gulls, or the chick dies soon after hatching.