Oblique Hatchetfish
Sternoptyx diaphana
- Least concern
- Card rarity: Common
- Fish

Sternoptyx diaphana, the diaphanous hatchetfish, is a species of deep sea ray-finned fish in the family Sternoptychidae. It is the type species of the genus Sternoptyx, and was first described by the French naturalist Johann Hermann in Der Naturforscher 1781.
Classification
- Class
- Actinopterygii
- Order
- Stomiiformes
- Family
- Sternoptychidae
- Genus
- Sternoptyx