The juvenile snail fish species was filmed swimming at 27,349 feet, about 8 kilometers below the sea surface, in the Izu-Ogasawara Trench in southern Japan.
The lead scientist of the study, Professor Alan Jamieson, said that snail fish can be observed at the maximum depth at which any fish can survive.
Similar snail fish have been observed before at a maximum depth of about 7 kilometers, and the new discovery broke the record for the deepest observed fish.
The previous deepest fish observation was in the Mariana Trench at 26,830 feet.
The snail fish is found in oceans around the world with over 300 different species currently known.
Species adapted to living in deeper waters can withstand the enormous pressure of the deep sea with the help of their gelatinous bodies.