Objective: To investigate the clinical application and preliminary results of 125I radioactive seeds brachytherapy in the comprehensive treatment of the pediatric soft tissue sarcoma in head and neck. Methods: A total of 24 pediatric patients with soft tissue sarcoma in head and neck were treated at Peking University School of Stomatology from April 2012 to July 2015. The data was collected and analyzed through statistical methods, which included the pathological type, gender, age, tumor location, volume, treatment and the clinical results after the application of 125I radioactive seeds brachytherapy. Results: Among the 24 patients, there were 18 patients of rhabdomyosarcoma, 2 Ewing's sarcoma, 2 fibrosarcoma, 1 synovial sarcoma and 1 malignant fibrous histiocytoma. After a follow-up of 9-48 months, 1 case of temporal rhabdomyosarcoma was observed to have a progression to the the lateral cranial base at the time of 12 months, 2 cases realized local control and systemic progression, the rest were completely relieved, and there was no recurrence during the follow-up period.The Kaplan-Meier survival analysis showed that the 1-year and 3-year local control rate were both 94.1%, the 1-year and 3-year event-free survival rate were 87.4% and 77.7%. Conclusion: The preliminary results indicate that 125I radioactive seeds brachytherapy play a very important role in the improvement of the local control rate and survival quality of the pediatric soft tissue sarcoma patient in head and neck, and it's a minimally invasive treatment with the advantage of accuracy andsmall side effects.