| Named By: | Andrews in 1901 |
| Time Period: | Priabonian, 37-35 Ma |
| Location: | North Africa, including Algeria, Egypt and the southern Sahara. Pakistan - Khadro Formation |
| Size: | Estimated between 9.3 and 10.7 meters long |
| Diet: | Carnivore |
| Fossil(s): | Specimens of 3 individuals |
| Classification: | | Chordata | Reptilia | Squamata | Serpentes | Madstoiidae | |
Gigantophis garstini is an extinct giant snake. Before the Paleocene constrictor genus Titanoboa was described from Colombia in 2009, Gigantophis was regarded as the largest snake ever. Gigantophis lived about 40 million years ago in the northern Sahara, where Egypt and Algeria are now located.