Lymphangioma is a benign tumor resulted from abnormal communication between large dermal lymphatic channels and central lymphatic system. The tumor is encountered more often in the neck and axilla and less often in mediastinum, omentum, retroperitoneum, and scrotum. It rarely developes at urogenital system, and there has been no previous description of lymphangioma involving the bladder wall in Korea. We report a case of 35-year-old female with infected huge lymphagioma ansing from pelvic cavity and involving bladder wall.