Wunderlich’s syndrome is classically defined as spontaneous nontraumatic bleeding confined to the subcapsular and perirenal space. Several causes such as renal neoplasm, vascular disease, infection, and underdiagnosed hematological disorders are involved. However, Wunderlich’s syndrome from hemorrhage of simple renal cyst is extremely rare in the literature. 37-year-old Korean man was transferred to our hospital because of aggravation of LLQ pain and fever. His previous past medical history included hypertensive intracranial hemorrhage and chronic kidney disease 3 year ago. His initial vital sign was as following; body temperature 37.5℃, blood pressure 140/90 mmHg, heart rate 102 times/minute, and respiratory rate 20 times/min. His initial hemoglobin was 8.8 g/dl and serum creatinine increased to 4.07 mg/dL. There was no abnormality on coagulopathy. He complained of severe tenderness on LLQ area. Enhanced CT revealed active bleeding and pseudoaneurysm in previous 2.7 cm sized simple cyst of left kidney connecting perirenal space leading to perirenal and retroperitoneal hematoma. Selective vessels embolization in left renal artery was done. His LLQ pain and fever subsided after embolization and renal function recovered to baseline level. He was following to our outpatient clinic without recurrence. We should keep in mind that Wunderlich’s syndrome was derived from spontaneous hemorrhage of simple renal cyst and selective arterial embolization could be a good choice to manage it.