This study was performed to compare the effects of neck dissection procedures on the prognosis of patients with pathological N1 (pN1) oral squamous cell carcinoma (OSCC), analyse factors affecting the prognosis, and provide a neck management strategy for clinical N1 (cN1) oral cancer. The study patients were divided into two groups according to the neck dissection: a selective neck dissection (SND) group (n = 85) and a radical or modified radical neck dissection (RND/MRND) group (n = 22). There was no statistically significant difference in recurrence rates at local, regional, and distant sites between the SND and RND/MRND groups. The 5-year overall survival was 68.3% for SND and 65.2% for RND/MRND patients (P = 0.590), while the 5-year disease-specific survival was 70.4% for SND and 75.7% for RND/MRND patients (P = 0.715). Histological grade and postoperative radiotherapy were independent predictors of the outcome for SND patients. For histological grade II/III cases, 5-year overall survival (P = 0.004) and disease-specific survival (P = 0.002) outcomes differed significantly between patients treated with and without postoperative radiotherapy, with worse survival for patients not treated with radiotherapy. Therefore, SND appears appropriate for cN1 OSCC patients, and postoperative radiotherapy is recommended for those with histological grade II or III tumours.