Objective: To compare hearing results in idiopathic sudden hearing loss patients treated with systemic steroids alone or combined intratympanic and steroids. Study Design: Prospective. Setting: Tertiary referral hospital. Patients: Idiopathic sudden sensorineural hearing loss patients. Interventions: The patients in the systemic therapy group received consecutive administration of 100 mg intravenous methylprednisolone in the first day, 80 mg/day oral prednisolone in 3 divided doses for the next 2 days, and continued with oral administration of steroids by tapering the dose 20 mg in every 2 days. The patients in the combined treatment group received intratympanic injection of methylprednisolone (an approximate dose of 0.5 ml of 125 mg/ml). A total of 5 injections on alternate days were performed. Main Outcome Measures: The mean and median PTA gains of systemic corticosteroid therapy (SCT) group were 7.5 and 5 dB at 5th day, 12.1 and 7.5 dB at 10th day, and 13.0 and 8.8 dB at 15th day. The mean and median PTA gains for combined treatment (CT) group were 12.5 and 7.5, 17.8 and 13.8, 21.8 and 20.0 dB, respectively. Results: Both the mean and the median PTA gains were statistically significantly different between SCT and CT groups. According to improved hearing results (more than 10 dB gain), there was statistically significant difference between SCT and CT groups. None of the patients had an important complication. Conclusion: The results of this study suggest that adding intratympanic methylprednisolone to systemic therapy increases the probability of hearing recovery in ISSHL patients. Copyright © 2011 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.