In total of 22, 954 patients who were seen at the Department of Urology, the University of Tokyo during the period of 1969 to 1976, 15, 998 had urological diseases, the number of urological diseases definitely diagnosed being 16, 789. They consisted of congenital anomalies (9.5%), tuberculosis (2.0%), venereal disease (1.2%), non-specific infection and inflammation (25.8%), neoplasms (15.9%), calculi (15.2%), foreign bodies (0.2%), trauma (1.0%), infertility (4.9%), adrenal diseases (0.6%) and others (23.7%). Sex and age distributions and etiologic factors in the diseases were determined.