This paper will focus on the topic of protected species of shellfish in the Adriatic Sea and the possible methods that can protect them. The bivalves, Bivalvia, belong to the mollusk phylum, Mollusca. 240 species of shellfish are known in the Adriatic Sea. This paper concentrates on 6 species of shellfish in the Adriatic Sea, namely: Pinna nobilis, Lithophaga lithophaga, Pholas dactylus, Atrina pectata, Atrina fragilis and Pinna rudis. These species are protected in various ways, such as conventions, for example: CITES, the Berne Convention and the Barcelona Convention, or by law. These species of shellfish need to be protected for a number of reasons. Some of these reasons are habitat devastation, hunting, sea pollution, global warming, parasitic microorganisms, etc. The noble pen shell (Pinna nobilis) is the most endangered of these species and is on the IUCN Red List of Critically Endangered Species. In addition to hunting and habitat devastation, this species has been threatened in recent years by the parasite Haplosporidium pinnae, which has only been found in dead or dying individuals. Lithophaga lithophaga and Pholas dactylus are endangered due to hunting and habitat devastation. Namely, these species live endolithically, which means that their habitat must be destroyed in order to reach the individuals. Other species, Atrina pectinata, Atrina fragilis and Pinna rudis, are endangered due to anthropogenic pressure (habitat destruction and/or hunting).