Marine species trafficking covers a range of illegal activities around the collection, transport and sale of protected marine-dwelling wildlife. Similarly to illegal wildlife trade generally, it takes place in contravention of national laws and particularly laws under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). 

Commonly trafficked species include: corals, tropical fish, giant clams, seahorses, shark fins, sea cucumbers, marine turtles, fish swim bladders, eels, baby lobsters, abalone and caviar.

Marine species are in demand globally for food, medicine, as jewellery, decorative objects, the pet trade and for zoos and aquariums.