Objective To identify the level and determinants of loneliness in patients with nasopharyngeal carcinoma receiving concurrent chemoradiotherapy, and to provide reference for targeted intervention. Methods A total of 252 patients with nasopharyngeal carcinoma receiving concurrent chemoradiotherapy were surveyed by using a general information questionnaire, Cancer Loneliness Scale, Fear of Progression Questionnaire-Short Form, and Cancer Fatigue Scale. Results The score of cancer loneliness was (19.82±3.03). Multiple linear regression analysis showed that age, housing status, number of symptoms, cancer-related fatigue, and fear of disease progression were influencing factors of loneliness (adjusted R2=0.552; P<0.05, P<0.01). Conclusion Patients with nasopharyngeal cancer experience moderate level of loneliness. Nursing staff should pay attention to this issue, particularly those who are older, who live alone, who have coexisting complications, who experience fatigue and fear of disease progression, to perform early assessment and intervention aiming to alleviate their loneliness.