CONCLUSIONS The head and neck cancer patients with more co-morbidities and those dependent on tube feeding are at a high risk of severe infections during chemotherapy. Therefore, prophylaxis with colony-stimulating factors and/or antibiotics should be considered for those patients. OBJECTIVES To investigate the risk factors for severe infection during chemotherapy in head and neck cancer patients. METHODS A retrospective study was conducted of 129 patients with head and neck cancer who received taxane-based and platinum-based chemotherapy between 2008-2013. Logistic regression models were used to evaluate risk factors. RESULTS Febrile neutropenia occurred in 50 patients out of the 129 (39%), severe infections occurred in 24 patients (19%), and bacteremia in two patients (2%). In univariate analysis, low serum albumin levels and tube feeding were significantly associated with severe infections (p = 0.015 and < 0.001, respectively). In multivariate analysis, the odds ratios for a higher modified Charlson co-morbidity index and tube feeding were 2.80 and 9.74, respectively. These two were independent predictive factors for severe infections (p = 0.020 and 0.001, respectively).