 Currently, postoperative chemoradiation is recommended for head and neck squamous cell carcinoma with some poor prognostic feature, such as extracapsular spread of metastatic lymph node, or positive resection margin. Other patients may receive postoperative radiotherapy only, if they have other risk factors. In our previous study, if there are 3 or more minor risk factors, the 3-year recurrence rate was 55. This outcome was far inferior to patients who had minor risk factors less than 3. Thus, we believe that current postoperative radiotherapy is insufficient for patients with multiple minor risks. A clinical trial should be raised to help these patients. However, the patient number of this group is not enough for large scale, phase 3 trial. So we arranged this phase II trial of postoperative chemoradiation to test and prospectively observe the treatment outcome. 