Unexpected fatal events in patients with head and neck cancers undergoing concurrent chemoradiation therapy are a clinical concern. Malnutrition, which is reported frequently in head and neck cancer patients, are associated with immunity derangement. The purpose of this study was to identify risk factors for early death of patients undergoing chemoradiation. We retrospectively analyzed the records of 194 stage III, IVA, and IVB head and neck cancer patients who were treated with chemoradiation between 2007 and 2009. We defined early death as death while receiving chemoradiation or within 60 days of treatment completion. Risk factors for early death were tested using univariate and multivariate analyses. Fourteen patients (7.2 %) experienced early death, 78.6 % of whom died of infection. Univariate analysis revealed significant correlations between early death and several pretreatment variables, including Eastern Cooperative Oncology Group performance status (PS) >1, hemoglobin <10 g/dL, albumin <3 g/dL, body mass index (BMI) <19 kg/m(2), and peripheral blood total lymphocyte count <700/μL. Multivariate analysis showed that PS >1, BMI <19 kg/m(2), and peripheral blood total lymphocyte count <700/μL were independent variables associated with early death. Poor performance status and malnutrition before chemoradiation independently predict early death in locally advanced head and neck cancer patients undergoing chemoradiation. Cautious management of head and neck cancer patients with these risk factors is required throughout chemoradiation period.