Two hundred fourteen of 218 American eel, AnguiUa rostrata, from brackish portions of Cooper River, South Carolina, were infected with 1 or more of 22 helminth species representing 4 classes: Trematoda, Cestoda, Nematoda and Acanthocephala. Larval nematodes (Contracaecum sp.) predominated, infecting 95% of eels examined. Seasonal, size- and age-related variations in levels of parasitism by trematodes and cestodes are discussed. Six new host and 7 new locality records are established.