: We reported a case of carotid artery stenosis with stroke symptoms detected in a patient with lung cancer after radiotherapy. The patient was a 58-year-old male with a complaint of \"a single episode of temporary amaurosis in the right eye for 10 minutes". The clinical diagnosis at admission, after consideration of the patient's age, medical history, and auxiliary examination results, was as follows: lung cancer; right common carotid artery stenosis; left common carotid artery stenosis; left vertebral artery stenosis; and right subclavian artery occlusion with right subclavian steal syndrome (Grade 3). Carotid angioplasty and stenting (CAS) were subsequently performed. During the 6-month follow-up, we observed no episode of temporary vision loss or other signs of stroke. Clinicians should pay great attention to delayed radiation-induced carotid stenosis. It is recommended that patients with a history of radiotherapy should undergo regular color Doppler ultrasound examination of the cervical region to diagnose, prevent, and treat RICS in an expedient fashion. This approach should improve survival rate and quality of life.