| Named By: | Louis Agassiz in 1843 |
| Time Period: | Late Cretaceous, 100-82 Ma |
| Location: | Worldwide |
| Size: | Up to 7 meters long |
| Diet: | unavailable |
| Fossil(s): | Usually teeth, but some impressions revealing the cartilaginous skeleton are also known |
| Classification: | | Chordata | Chondrichthyes | Elasmobranchii | Selachimorpha | Lamniformes | Cretoxyrhinidae | |
| Also known as: | | Ginsu shark | |
Cretoxyrhina mantelli was a large shark that lived about 100 to 82 million years ago, during the late Cretaceous period. It is nicknamed the Ginsu shark in reference to the Ginsu knife, since it fed by slicing into its victims with its knife-sharp teeth. It had no common name in the early literature, although over 30 synonyms were assigned to it. Its genus name is creto- (for "Cretaceous") prefixed to Oxyrhina ("sharp-nosed"), its original name.