ObjectiveTo investigate the incidence and influencing factors of healthcareassociated infection (HAI) in inpatients with nasopharyngeal carcinoma during radiotherapy period. MethodsThe occurrence of HAI among patients with nasopharyngeal carcinoma in a tertiary firstclass cancer hospital in Jiangsu Province between July 2012 and June 2014 were analyzed retrospectively. ResultsA total of 1 396 patients were investigated, the incidence of HAI was 2.29%, case incidence of HAI was 2.44%. The most common infection site was oral mucosa (n=24，70.59%）, and most infection occurred 2-4 weeks after the start of the radiotherapy. A total of 38 pathogenic isolates were isolated, 24（63.16%） were grampositive bacteria，12 （31.58%）were gramnegative bacteria，and 2（5.26%）were fungi. Incidences of HAI were high in patients >50 years old, with chemotherapy, length of hospital stay>60 days, and used at least 2 kinds of antimicrobial agents (all P<0.05). ConclusionPrevention and control of HAI in patients with nasopharyngeal carcinoma during radiotherapy period should be strengthened, especially for the elderly, patients with chemotherapy, long length of hospital stay, and extensive use of antimicrobial agents.