A 32-yr-old, previously healthy man with severe chest pain of sudden onset was found to have purulent pericarditis and pleural effusions. Several days later, an esophagogram revealed a perforation of the thoracic esophagus. Endoscopy showed a picture highly suggestive of a late stage of an extensive herpes simplex virus (HSV) esophagitis. Biopsies revealed evidence of massive HSV infection, confirmed by immune microscopy and virus culture. At surgery, a mediastinal abscess was found, and an esophageal perforation was identified. These findings suggest that the etiology of the perforation was an unusually severe herpetic infection. To our knowledge, HSV esophagitis has not previously been implicated as the cause of spontaneous esophageal perforation.