Background: Head and neck cancer (HNC) poses a significant threat to both psychological and physical health. This study aimed to depict the anxiety status of Chinese newly diagnosed nonmetastatic HNC patients during radiotherapy (RT) and to examine predictors of anxiety symptoms. Methods: Newly diagnosed nonmetastatic HNC patients who received RT at the Radiation Therapy Center of Sun Yat-sen University Cancer Center from August 23,2023 to August 24,2023 were recruited into this study. Using Zung Self-Rating Anxiety Scale (Zung SAS) to screen anxiety. Twenty-four common acute therapeutic toxicities (18 patient-reported and 6 clinician-rated) were assessed according to European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Head and Neck 35 (EORTC QLQ-HN35) and Common Terminology Criteria for Adverse Events, fifth version (CTCAE V5.0). Chi-square (χ²) test and multivariate binary logistic regression stepwise forward selection: likelihood ratio (LR) method were applied to identify factors associated with anxiety. Results: A total of 457 patients were included ultimately. Up to 29.10% of the patients showed varying degrees of anxiety and the average SAS standardized score was 45.66 ± 8.83. Chi-square test manifested that sex, annual household income, fatigue, anorexia, nausea, vomit, pain, dysphagia, sense problems (smell and taste), speech problems, trouble in social eating, trouble in social contact, sexual frustration, teeth problems, difficulty in opening mouth, xerostomia, sticky saliva, coughing, feeling ill, use of analgesics, use of nutritional supplements and weight loss were related to anxiety (p< 0.05). But multivariate logistic regression only demonstrated fatigue (OR = 3.696, 95% CI = 2.096-6.519), speech problems (OR = 3.247, 95% CI = 1.554-6.783), sexual frustration (OR = 2.029, 95% CI = 1.232-3.341), nausea (OR = 3.075, 95% CI = 1.807-5.234), feeling ill (OR = 2.283, 95% CI = 1.215-4.291), use of nutritional supplements (OR = 1.930, 95% CI = 1.136-3.280) and difficulty in opening mouth (OR = 3.007, 95% CI = 1.081-8.363) as independent predictive factors of anxiety. Conclusions: The Chinese newly diagnosed nonmetastatic HNC patients suffered greatly from anxiety during RT. This study identified the predictive contribution of sociodemographic and clinical characteristics and 24 common acute therapeutic toxicities to the vulnerability to anxiety, which can provide evidence and reference for medical staff to carry out psychological intervention.