Five hundred and fifty patients treated for carcinoma of the uterine cervix at the Department of Therapeutic Radiology, Seoul National University Hospital from 1979 to 1986, were analyzed retrospectively for late bladder complications. of them, 468 patients received primary radiotherapy for the cervix cancer in intact uterus, and the other 52 patients were treated postoperatively. The cumulative incidence of radiation induced bladder complication of grade 2 or 3 was 2.5% at five years. The mean bladder dose for the group of patients with complication was higher than that of the group without complication, and the difference was statistically significant(p<0.01). But relationship between mean bladder dose and severity of complication was not found. The frequency of complication(grade I,II,III) increased as a function of radiation dose to bladder from 5.0% for patients with bladder dose less than 6,500 cGy to 27.7% for patients with bladder dose higher than 8,000 cGy. Among various factors, the age of patient and the distance between ovoids turned out to have significant effect on the complication.