Abstract: Radiotherapy combined with chemotherapy is the main treatment for stage Ⅱ-Ⅳa nasopharyngeal carcinoma (NPC). In the era of intensity-modulated radiation therapy, the timing and implementation of chemotherapy are still controversial. In the past, the clinical guidelines for NPC generally described the specific radiotherapy technology, dose fractionation and the specific scheme of combined application of radiotherapy and chemotherapy, and may lack specific practical guidance. The joint international guidelines for NPC by CSCO and ASCO elaborates the mode and specific implementation recommendations of radical chemoradiotherapy for stage Ⅱ-Ⅳa NPC. This article aims to interpret the specific details of the guideline.