Intro: Aim of this study is to determine whether Thrombin Time (TT) could be used as diagnostic biomarkers and predict the prognosis for sudden sensorineural hearing loss (SSNHL). Methods: 61 diagnosed SSNHL patients and 65 persons undergoing physical examination were recruited. Data of patients’ background, clinical course, laboratory findings were collected. SSNHL patients were divided into the effectual and ineffectual group according to the hearing recovery of the treatment and assessed by binary logistic regression. Receiver operating characteristic (ROC) analysis was used for the best discriminating cut-off value of the biomarker with the corresponding sensitivity and specificity was calculated. Results: The SSNHL group exhibited prolonged TT (19.11±1.12s) compared with control group (17.58±2.18s, p<0.001). Binary logistic regression analysis found a significant positive association between TT and SSNHL with an odds ratio (OR) 1.769 [95% confidence interval (CI) 1.344-2.330, p<0.001] in the unadjusted model. Even after adjustment using variables included in the multivariate models, TT was significantly predictive of SSNHL.A TT cutoff value of 17.65s provides optimal separation between SSNHL patients and controls in ROC analysis (AUC 0.773, 95% CI 0.689-0.856; sensitivity, 0.918; and specificity, 0.569). TT in effective group of the SSNHL patients was shorter (18.76±1.06s) than that in ineffective group (19.43±1.09s, p=0.018). The cutoff value of TT as progress predictors is 19.85s. The TT <19.85s showed higher effective rate 59.09% (26/44) than that 17.65% (3/17) of TT≥19.85s. Conclusion: TT is a potential biomarker of SSNHL and independently associated with the prognosis of SSNHL patients.