Emphysematous pyelonephritis (EPN) is a life-threatening bacterial infection and should be treated rapidly and carefully. We report a case of EPN with complete duplication of the left urinary tract. A 68-year-old woman was admitted to our hospital complaining of high-grade fever and left flank pain. An abdominal computed tomography scan showed gas was presented in the renal parenchyma, not only the pelvis and ureter. Based on these findings, a diagnosis of left EPN was made. A partial nephrectomy of the affected left upper pole moiety was performed and the patient underwent additional medical management. Other 83 cases of EPN from the Japanese literature were reviewed.