Aziz Nacib Ab'Sáber (Portuguese pronunciation: [aˈziz naˈsib abˈsabeʁ]; October 24, 1924 – March 16, 2012) was a geographer and one of Brazil's most respected scientists, honored with the highest awards of Brazilian science in geography, geology, ecology and archaeology.

He received the Grand Cross in Earth Sciences of the National Order of Scientific Merit, the highest rank.

He made central contributions to biology, South American archaeology, and to Brazilian ecology, geology and geography.

[2] Ab'Sáber was the first person to classify scientifically the Brazilian and South-America territory in morphoclimatic domains.

He also contributed to the "Pleistocene refuge hypothesis", an attempt to explain the distribution of Neotropical taxa as a function of their isolation in forest fragments during glacial periods, which allowed populations to speciate.