This study was performed on 72 patients with head and neck squamous cell carcinoma. Total lymphocyte, natural killer cell and total lymphocyte subpopulation levels in peripheral blood were determined and the correlation of these levels with TNM and Histopathologic Malignancy Grading (HMG) systems were investigated. TNM and HMG systems, which are two important prognostic indicators, were significantly correlated whereas total lymphocyte, natural killer cell and total lymphocyte subpopulation levels in peripheral blood had no correlation with TNM and HMG scores.