Bluefin tuna or blue fin tuna may refer to one of the following species of tuna:
- Northern bluefin tuna
- Pacific bluefin tuna, Thunnus orientalis, found widely in the northern Pacific Ocean and locally in the south
- Atlantic bluefin tuna, Thunnus thynnus, found in both the western and eastern Atlantic Ocean, as well as the Mediterranean Sea
- Thunnus tonggol, commonly known as Longtail tuna, found in tropical Indo-West Pacific waters
- Southern bluefin tuna, Thunnus maccoyii, found in open southern hemisphere waters of all the world's oceans