목적: The objective of this study was to delineate whether the metabolic syndrome (MetS) contribute to the hearing outcome in patients with idiopathic sudden sensorineural hearing loss (ISSNHL). 방법:A total of 120 ISSNHL patients enrolled in this study between July 2012 and December 2014. Patients were divided into two groups according to the presence or absence of MetS at admission group I (presence, n=40) and group II (absence, n=80). In this study, metabolic syndrome was diagnosed according to standards suggested by the AHA/NHLBI ATP III 2005, and abdominal obesity ( 90 cm in men and 85 cm in women for Korean) was diagnosed according to standards set forth by the Korean Society for Study of Obesity. Recovery rate of the hearing was assessed by American Academy of Otolaryngology Head and Neck Surgery (AAO-HNS) Clinical Practical Guidelines. 결과:A recovery of the mean PTA in group II was significantly better than group I 25.6 dB in group I and 33.0 dB in group II (P = 0.004). And, no recovery according to Siegels criteria was more frequently observed in group I - 16 (40.0%) of 40 group I patients and in 12 (14.3%) of 80 group II patients (P = 0.028). But, any factors of metabolic syndrome did not significantly correlate the hearing outcome in ISSNHL patients. 결론:The co-occurrence of the MetS in ISSNHL could be an indicator of worse hearing prognosis even though we choose appropriate treatments.