Immunosuppressive medications, frequently used to treat inflammatory bowel disease, have been linked to the development of Epstein-Barr virus (EBV)-associated lymphoproliferative disorders (LPD). We describe a case of an EBV-positive mucocutaneous ulcer involving the palate in an elderly woman with inactive Crohn's disease. This patient had been on high-dose azathioprine for a decade. Following diagnosis of her LPD and discontinuation of azathioprine, her oral ulcers resolved completely.