Background: To investigate the therapeutic efficacy of computed tomography (CT)-guided permanent percutaneous implantation of iodine-125(125I) for treating recurrent head and neck cancers.Methods: Thirteen patients with recurrent head and neck cancer (previously treated with a total cumulative dose exceeding 100 Gy) were included in this study.125I seeds were implanted into recurrent head and neck lesions by CT-guided needle puncture.Treatment responses were evaluated during follow-up by contrast-enhanced CT.Survival was analyzed using the Kaplan-Meier method.Results: The tumor response rate was 84.0%.The overall median control time was 24.0 months.The local control rate was 57.8% and 34.5% at 1 and 2 years,respectively.The overall 1-and 2-year survival rates were 61.9% and 38.1%,respectively.No serious complications were observed postoperatively and during the follow-up period.Conclusion: Ultrasound-guided brachytherapy using 125I seed implantation is safe and effective for treating recurrent head and neck cancer.