Five fatal cases of disseminated strongyloidiasis were identified in Erythrocebus patas caged singly or in groups of two to four in an indoor research facility. This is the first report of fatal hyperinfective strongyloides infection in a species other than great apes and man. Severe pulmonary hemorrhage, duodenitis, and proximal colitis with microscopically demonstrable larvae in affected tissues were the key necropsy findings. E . putus is an available, suitable model for the study of disseminated strongyloidiasis.