Nowday, ionizing radiation is one of the methods eradicating the uterine cervical malignancy. However radiation alone or in combination with surgery have an effect on normal tissue as well as the malignant cells, and their changes have been well described in other countries. Unfortunately, the history of radiation modality for cancer treatment is relatively short and the reports about radiation induced changes are limited in our country. We evaluated the radiation-induced changes in cervico-vaginal smears of 107 uterine cervical cancer patients obtained from March, 1985 to October, 1987. Most patients had been received 5,400 Rads of external radiation and intracavitary radiation. Patient's age ranged from 30 to 67 years old. Of 107 cases, 24 cases were normal, 72 cases showed benign radiation changes, 7 cases revealed radiation dysplasia, and residual and recurrent carcinomas found in one and 3 cases, respectively. Cytoplasmic and nuclear enlargement were the most common and noted in 57 and 38 cases, respectively. Vacuolization and polychromasia of the cytoplasm were identified in 43 and 30 cases, respectively. The most common histiocytic change was multinucleation, which was found in about one third. The radiation changes of the cytoplasm and nuclear enlargement persisted for a long time after completion of radiation, however, nuclear degeneration and multinucleation gradually disappeared after 6 months. The inflammation in background prolonged for a long time but degeneration disappeared after 6 months. The biologic significance of post-radiation dysplasia could not evaluated because of short follow up period.