Presence of marine mammal nematodes in Turkey is poorly known. One bottlenose dolphin (Tursiops truncatus) and four harbour porpoises (Phocoena phocoena) stranded on the Turkish coast were examined at necropsy between 2009 and 2012. Harbour porpoise stranded from Marmara Sea were only infected by three species of lungworms (Metastrongyloidea): Stenurus minor, Halocercus invaginatus and H. taurica. Anisakid, pseudaliid, filarioid and spirurid nematodes were not found in the investigated organs and alimentary canal from harbour porpoises and bottlenose dolphin from Black Sea. The present study represents the first geographic record of H. taurica from Turkish waters. Moreover, S. minor is the first and new host record of harbour porpoise from the coast of Black Sea. Additionally, pathological findings associated with lungworms are also presente.