Noise-Induced Hearing Loss (NIHL) is one of the most common occupational disorders. Different characteristics of environmental or occupational exposure as well as individual differences trigger NIHL. This study was aimed to evaluate the effect of blood groups, Rhesus (Rh) antigen, and serum cholesterol, triglyceride, and glucose level as risk factors of NIHL. A total number of 1900 drivers who attended the occupational medicine clinic of Baharloo Hospital for the annual health-test of drivers were entered to the study. Pure tone audiometry test was performed for all subjects, blood group, serum cholesterol, triglyceride, and glucose levels were measured. Coles, Lutman, and Buffin’ s (2000) algorithm were used to identify notched audiograms. A total number of 752 out of 1900 drivers (39. 6%) were identified with notched audiograms. No significant difference was observed in serum glucose, cholesterol, and triglyceride between the two groups according to the presence of high-frequency notches. The distribution of blood groups in the study group was as follows: O (36. 7%), A (34. 1%), B (22. 7%), AB (6. 5%). There was no significant relationship between blood groups and hearing thresholds or between Rh antigens and high-frequency notch. The results of this study was proved the relationship between age and hearing loss, but did not demonstrate any association between blood groups, Rh antigen, serum cholesterol, triglyceride, glucose levels, and NIHL.