Isolate esophageal ulcer caused by Geotrichum candidum in a case of AIDS. We report the case of a 29-year-old white man, AIDS affected, presented with odynophagia, dysphagia and chest pain. X-ray and endoscopic study revealed an isolated esophageal ulcer whose culture demonstrated to be caused by Geotrichum candidum. This etiologic agent was not previously described in this kind of lesion.