Introduction: Red Cell Distribution Width (RDW) may indicate inflammatory alterations and patient's health general impairment. It is believed that RDW may play an important role in the prognostic evaluation of patients presenting neoplasia. Objective: To evaluate the isolated prognostic impact of Red Cell Distribution Width (RDW) on the overall survival of patients diagnosed with Head and Neck Squamous Cell Carcinoma (HNSCC). Methods: We evaluated, retrospectively, 203 patients undergoing treatment for head and neck squamous cells in a period of five years. Clinical, pathological, and therapeutic data were collected and individually associated to the outcome of each case. Through multivariate analyses by logistic regression, we identified which elements have the greatest impact on the overall survival of patients diagnosed with HNSCC and how the RDW behaved as a prognostic factor. Results: After establishing statistically relevant risk factors in a univariate analysis, we checked which elements remained relevant after removing the interference of the therapeutic approach in the overall survival. In all analyses, it was found that RDW, as well as staging factors at the time of diagnosis, had an impact on the overall survival of HNSCC patients regardless of the therapeutic approach adopted. Conclusion: Due to the significant association between increased RDW values and unfavorable outcomes in the survival of HNSCC patients, it is observed that the element behaved as an independent prognostic factor and its use is pertinent in clinical practice. [ABSTRACT FROM AUTHOR]