Incidence. The number of patients with urolithiasis w as 283 which occupied 16.2 % of the total number of the patients who visited our department. Regional Distribution. Kidney stone was seen in 140 cases (37.9 %), ureteral stone in 171 cases (46.3 %), bladder stone in 27 cases (7.3 %), prostatic stone in 25 cases (6.8 %), and urethral stone in 6 cases (1.6 %). Age, Sex and Side. The high e st incidence was seen in persons of the third decade which occupied 55.9 %. Urolithiasis occurred more frequently in the male than in the female. No predilection in the affected side was observed. Symptoms. The chief complaints were pain i n the flank and abdomen, lumbago and hematuria. Renal colic was experirnced in 35.7 % of the patients with kidney stone and in 71 % of the patients with ureteral stone. Treatment. Operative treatment was mainly carried out for the stones in the upper urinary tract, but rapid diuresis was proved to be effective.