Doxycyline can cause esophagial irritation if not taken with sufficient water or just before going to sleep. In this case report, a 47 year-old female patient who had been prescribed doxycyline for brucellosis is presented. She was admitted with retrosternal pain and dysphagia which had started after taking the 4th oral dose of the drug. Endoscopic examination revealed solitary ulceration at 30th centimeter of the esophagus. The diameter of the lesion was 2x1 cm. Sucralphate and lansoprosole therapy was given to the patient. With this therapy the clinical symptoms and ulcerative lesion disappeared.