A 2.5-year-old male Chinchilla presented with a 10-day history of weight loss, lethargy, and abnormal stools. Radiographs demonstrated peritoneal effusion, diffuse bronchointerstitial pulmonary markings, and suspicion of a cranial mediastinal mass. Humane euthanasia was elected, and a necropsy was performed. On necropsy, multiple white, well-demarcated nodules of various size were identified within the walls of the gastrointestinal tract and lung parenchyma. A similar discrete mass was found at the heart base, and there was enlargement of the mesenteric lymph nodes. Impression smears of the heart-based mass and several nodules demonstrated high numbers of yeast resembling Histoplasma spp. Histologic examination of lesions within the intestinal wall and mesenteric lymph nodes demonstrated an abundance of yeast organisms with surrounding inflammation. The findings were consistent with disseminated histoplasmosis. Histoplasma spp. infection has been rarely reported in chinchillas and other exotic mammal species.