Squamous cell carcinoma of the head and neck (SCCHN) have been reported to be related to both genetic and environmental factors, including alcohol consumption and alcohol-metabolizing enzymes such as alcohol dehydrogenase (ADH). We conducted a hospital-based, case-control study including 50 cases with diagnosed SCCHN and 700 controls with non-neoplastic conditions such as upper respiratory tract infection. The genomic DNA was isolated from peripheral blood leukocytes. The ADH1C*1 wild-type and ADH1C*2 variant alleles were analyzed with an RFLP method by using Sspl as restriction enzyme. The ADH1C*1 allele frequencies were 0.89 (CI95% = 0.84-0.91) in controls and 0.77 (CI95% = 0.71-0.83) in cases, and respective frequencies of the ADH1C*2 allele were 0.11 (CI95% = 0.07-0.14) and 023 (CI95% = 0.17-0.29) among controls and cases (P = 0.01). The ADH1C*1/*1 genotype frequency was significantly higher in the control group (77%) compared to that of the cases (58%) (P = 0.02). These findings suggest that a lower presence of ADH1C*1 allele is associated with SCCHN, but larger numbers are needed to more precisely estimate the interaction, if any, with ADH1C. Interestingly, the ADH1C allele and genotype frequencies in our control group living in Denizli were significantly different compared to a previously published report from healthy volunteers living in Ankara (P < 0.0001).