Inclusion Criteria:  Age: 18 to 75 Gender: Male and female ECOG Score: 0-2 Histologically confirmed primary oral squamous cell carcinoma (including tongue, gingival, buccal, oral base, hard palate, posterior molar area) Clinical stage III/IVA (cT1-2/N1-2/M0 or cT3-4a/N0-2 /M0, AJCC 8th) The combined positive score (CPS score) of PD-L1 expression > 10 Has signed informed consent  Exclusion Criteria:  Toxicity of ≥ grade 2 (CTCAE 5.0) that has not subsided due to previous anticancer therapy Obvious cardiovascular abnormalities (such as myocardial infarction, superior vena cava syndrome, ≥ grade 2 heart disease diagnosed according to the NYHA classification criteria within 3 months prior to enrollment) Active severe clinical infection (> NCI-CTCAE Version 5.0 level 2 infection) Uncontrollable hypertension (systolic blood pressure > after antihypertensive medication; 150mmHg and/or diastolic blood pressure > 90mmHg) or clinically significant (such as activity) cardiovascular disease, such as cerebrovascular accident (≤ 6 months before screening), myocardial infarction (≤ 6 months before screening), unstable angina, congestive heart failure rated class II or above by NYHA, or severe arrhythmias that cannot be controlled or have a potential impact on trial treatment Blood routine examination: WBC < 3,000/mm3, hemoglobin < 8g/L, platelet < 80,000/mm3 Liver function: ALAT/ASAT > 2.5 times the normal upper limit, bilirubin > 1.5 times the normal upper limit Renal function: serum creatinine > 1.5 times the normal upper limit Has a history of maxillofacial and neck radiotherapy Pregnant or lactating women Participation in other clinical studies within 30 days prior to enrollment Other conditions that the investigator considers inappropriate for participation