Inclusion Criteria:  (1) Received radiation therapy due to head and neck cancer. (2) The patient have depression symptoms (PHQ-9 score ≥ 8) and meet the ICD-10 (version 2019) diagnostic criteria. (3) Age>/= 18 years and age</=65. (4) Estimated life expectancy ≥ 12 months. (5) Constant caregivers who well understand and have willingness to sign a written informed consent document.  Exclusion Criteria:  (1) The researcher believe that the subjects have the tendency of suicide, self mutilation or the score of "suicide concept" in item 10 of MADRS was ≥5, or they had committed suicide, self mutilation within 6 months before enrollment; (2) History of depressive disorder before radiotherapy for head and neck tumors; (3) History of other serious mental disorders, such as generalized anxiety disorder, drug and alcohol abuse, etc; (4) History of central nervous diseases such as Alzheimer's disease, Parkinson's disease, Stroke, uncontrolled epilepsy, etc., which lead to emotional and cognitive impairment and other serious and uncontrolled systemic diseases (such as cardiopulmonary insufficiency, etc.); (5) Baseline Mini Mental State Examination (MMSE) score ≤ 23 points (University or above), MMSE ≤ 22 points (middle school), MMSE ≤ 20 points (primary school), MMSE ≤ 17 points (illiteracy); (6) The subject with brain metastasis; (7) Hematological examination of subject: White blood cell count < 3.5×10^9/L, Platelet count < 100×10^9/L, Hemoglobin < 110g/L, Abnormal range of coagulation function like fibrinogen < 1.5g/L, or other coagulation abnormalities with clinical significance； (8) Blood biochemical examination of patients: Total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT) > 2.0 x upper limit of normal value, Creatinine > 1.5x upper limit of normal value, Blood sodium < 130mmol/L; (9) The subject has a history of severe drug allergy or is known to be allergic to any excipient of the test drug; (10) The subjects who could not effectively complete the neuropsychological test during the follow-up.