We retrospectively analyzed the CT (10 cases) and MR (5 cases) findings in 10 patients with radiation-induced pulmonary injury. On CT studies, 8 cases showed fibrotic change and 6 of them also showed solid consolidation with bronchiectasis. The differential diagnosis of radiation-induced injury from residual or recurrent tumor was possible on CT studies which was impossible on plain chest radiograph (2 cases) or MR study(1 case). On MR studies, 4 cases showed solid consolidation with bronchiectasis and fibrosis. The signal intensity was siointense compared with that of the muscle on T1WI (5 cases), and hyperintense of PDWI and T2WI(3 cases). The lesions enhanced well on Gd-DTPA enhanced study (4 cases). The residual or recurrent tumor showed the same signal intensity and degree of enhancement with radiation-induced injury (2 cases). CT and MR are useful for the evaluation of the anatomic details of the large overlapped area of increased density of the radiation-induced pulmonary injury on plain chest radiograph. But MR study is not superior to CT on the differentiation of the residual or recurrent tumor and radiation-induced injury because the tumor may show the same signal intensity and degree of enhancement with radiation-induced injury.