Over a period of 4 mo, an entire collection of seven Pine Barrens treefrogs (Hyla andersonii) died or were euthanized after developing pallor, generalized edema, and coelomic effusion. Necropsy revealed large numbers of strongyloidid nematodes within the small intestines associated with a moderate mucosal hyperplasia. Strongyloides sp. parasitic females, representing a novel species, were isolated from the fixed intestinal tract. This case report represents the first full description of strongyloidiasis in a tree frog army and highlights the potential of Strongyloides spp. as a cause of rapid mortality events associated with protein-losing enteropathy in frogs.