Xanthogranulomatous cystitis is a rare benign inflammatory disease that develops from a urachal remnant or occurs in association with pelvic surgery. Because it manifests as an infiltrative tumor-like lesion arising from the mid-line along the bladder dome and anterior abdominal wall, it is not easy to differentiate from The authors encountered one case of xanthogranulomatous cystitis, diagnosed by means of surgery and pathologic examination, and we report the related ultrasonographic and CT findings.