To investigate the safety and efficacy of low-dose radiotherapy combined with chemotherapy and immunotherapy as neoadjuvant therapy for locally advanced oral squamous cell carcinoma (OSCC), and to explore whether low-dose radiotherapy can induce cross-presentation of tumor-specific antigens, enhance lymphocyte infiltration into the tumor microenvironment, and thereby amplify tumor-specific immune responses, ultimately improving the therapeutic outcomes of neoadjuvant chemoimmunotherapy.