Animal studies suggest that tumor necrosis factor (TNF) alpha blockers may pass to the inner ear in adequate concentration. In this prospective study, we aimed to evaluate the effect of infliximab on the inner ear hearing function in patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA). The patients with high disease activity, who were planned to begin infliximab for therapy by physical medicine and rehabilitation department, were referred to ear-nose-throat clinic for consultation. After physical and otoscopic examination, audiological tests were performed. Air conduction thresholds between 250 and 8,000 Hz, bone conduction thresholds between 500 and 4,000 Hz, pure tone average, speech discrimination scores, distortion product otoacoustic emission (DPOAE) were used to evaluate the hearing function. The tests were repeated 2 and 6 months after the initiation of the drug "infliximab." A total of 44 ears of 22 patients (17 males and 5 females) were evaluated. Fifteen patients had a diagnosis of AS, and seven patients had RA. After initiation of infliximab therapy, statistically significant improvement was observed in disease activity scores [Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) for AS, Disease Activity Score 28 (DAS-28) for RA] after 2 and 6 months (p < 0.05). We did not find any statistically significant difference between the air conduction thresholds, bone conduction thresholds, pure tone average, speech discrimination scores, and measurements of DPOAE before the initiation of treatment and after 2 and 6 months (p > 0.05). Any problem about the balance, vertigo, or dizziness was not reported from the patients during the treatment period. As a result, our study showed that there was no notable change or deterioration in the hearing function of the patients with AS and RA who were treated with infliximab. Further studies with higher number of patients with AS and RA and also with different TNF alpha inhibitors are needed to make more valid conclusion.