Like many sharks, the cookie-cutter shark is a carnivore. It attaches itself to its prey with its strong sucking mouth, and then twists about, using its sharp lower teeth to slice out a plug of flesh, which can sometimes be twice as deep as its diameter. It then uses its hook-like upper teeth to hold the plug, while the lower teeth scoop the plug out. Detaching, it swims away to enjoy its meal. It preys on deep water organisms, including crustaceans, squid, large bony fishes, cetaceans, and even large sharks. It is bioluminescent, able to emit a greenish light from its belly. It may use this light to attract the attention of potential victims (Compagno 1984, Roesch 1997).