BACKGROUNDEwing’s sarcoma (ES) is regarded as a skeletal tumor, with few instances of extra-skeletal ES. A primary ES in the ureter is extremely rare.CASE SUMMARYWe report the case of a 69-year-old woman who presented with intermittent flank pain and hematuria and was found to have a mass in the left ureter. Pathology of the excised mass indicated ES. The clinical treatment and pathologic characteristics in this case, and a review of the literature describing ES in the urinary system, are presented.CONCLUSIONDue to the rarity and malignancy of ES in ureter, early diagnosis and prompt surgical treatment are critical.