Introduction: In this study, we examined the role of immunological factors on sudden sensory neural hearing loss (SSNHL). Materials and Methods: This prospective case-controlled study was performed in patients with SSNHL who referred to the ear, nose, and throat (ENT) ward. Fifty-six patients with SSNHLoccurring within a 72-hr period were selected as the case group and 56 participants who had no recent history of disease were assigned to the control group. Mean levels of immunological factors including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), antinuclear antibody (ANA), anti-neutrophil cytoplasmic antibody (ANCA) (C, P), anti-cyclic citrullinated peptide (anti-CCP), DSM, hemoglobin (Hb), complement component 3 (C3), and complement component 4 (C4) were evaluated in the blood samples in each group. Results: There were 31 male and 25 female participants in the control group, while the case group had 26 male and 30 female participants. The mean age of the participants was 36.2 ± 13.4 years in the control group and 40.80 ± 13.37 years in the case group. The two groups differed significantly in terms of mean ESR, ANA, C3, C4 and monocytes, with higher levels in the case group (P<0.05). However, differences in mean CRP, anti-Ds DNA, Hb, anti-CCP, white blood cells (WBC), neutrophils, lymphocytes, eosinophils, and platelets were not statistically significant between the case and control groups (P> 0.05). Conclusion: Because some of the immunological factors investigated in this study were significantly higher in patients with SSNHL, it can be concluded that there is an association between these immunological factors and SSNHL. Further studies are recommended to accurately determine the effect of these factors on the development of SSNHL and its treatment.