Purpose The objective of this study was to reveal the long-term sequelae in survivors of childhood and adolescent nasopharyngeal carcinoma after radiation therapy. Methods and Materials We reviewed the medical records of patients aged Results A total of 94 patients survived. They had a median follow-up time of 10 years (5-27 years). Compared with the CI of survivors treated with conventional radiation therapy treatment, the CI of xerostomia, dysphagia, and chronic otitis media was significantly decreased in the survivors treated with intensity modulated radiation therapy treatment. The CI of blurred vision in patients younger than 10 years and in patients 10 to 18 years old were 33.3% and 2.3%, respectively (P = .006). Survivors who received a nasopharynx dose >72 Gy, compared with a nasopharynx dose of 60 to 72 Gy, had a significantly higher CI of hearing loss (P = .008), lalopathy (P = .013), and cranial nerve injury (P = .029). We also had records of height, weight, education level, annual income, marital and fertility status, and menstruation state for 59 of the survivors. Twenty-two percent of the survivors had a body mass index lower than 18.5. Among the female survivors, 11 of 16 (62.5%) had menstrual or fertility problems. Conclusions Compared with convention radiation therapy treatment, intensity modulated radiation therapy treatment can potentially ameliorate xerostomia, dysphagia, and chronic otitis media. In addition, patients younger than 10 years had a higher CI of blurred vision. Moreover, a dose of more than 72 Gy to primary tumor increased the CI of hearing loss, lalopathy, and cranial nerve injury.