A 37-yr-old male chimpanzee (Pan troglodytes) was evaluated for intermittent diarrhea, scrotal swelling, and lethargy of 2 days duration. Physical examination revealed marked swelling of the scrotum and perineal tissues with mild pitting edema and crepitus. Computed tomography revealed a mixed gas and soft-tissue density extending from the caudal ventral subcutaneous tissues caudally to the scrotum and perineal tissues. Surgical exploration and castration were performed to establish drainage, and culture revealed a polymicrobial infection. A diagnosis of scrotal and fascial plane abscessation consistent with Fournier's gangrene was made. Although castration with open drainage was performed, the animal died 36 hr after surgery. Postmortem examination and histopathology revealed necrotizing fasciitis of the penis, vaginal tunic, and subcutaneous perineal and perianal tissues.