Emphysematous cystitis is a urinary tract infection with gas formation. Because of life-threatening complications, early diagnosis and treatment of emphysematous cystitis are essential. Many predisposing factors have been described, such as diabetes mellitus and neurogenic bladder. Hydronephrosis without an obstructive lesion has been reported in some emphysematous cystitis cases. In this case report, a 74-year-old female patient was diagnosed with emphysematous cystitis and bilateral hydronephrosis without any predisposing factor. We present the characteristics of the case in this report.