<h4>Objective</h4>To explore the efficacy and safety of adjuvant radiotherapy and sequential programmed cell death protein-1 (PD-1) inhibitors in high-risk patients after oral cancer surgery.<h4>Methods</h4>This single-center, retrospective study included high-risk oral cancer patients who received adjuvant therapy at The First Affiliated Hospital of Nanchang University from January 2013 to December 2024. The gene discussed is PDCD1; the disease is lip and oral cavity carcinoma.