Objectives To investigate the correlation between blood total cholesterol (TC) and prognosis of idiopathic sudden sensorineural hearing loss (ISSNHL) and to provide references for clinical treatment and prognosis assessment. Methods We included 232 ISSNHL patients with total deafness in Wenzhou Central Hospital from June 2015 to March 2017 using a prospective cohort design. Recording information including age, gender, hypertension, diabetes mellitus, vertigo, level of blood total cholesterol (TC), level of triglyceride (TG), level of low-density lipoprotein (LDL-C) and LDL/HDL ratio (LDL-C/HDL-C) were collected. Correlation between the prognosis of ISSNHL and blood total cholesterol were analyzed by univariable and multivariable logistic regression analysis. Results The clinical effective rate of patients with TC ranging from 5.2 mmol/L to 6.2 mmol/L was higher than that of patients with TC lower than 5.2 mmol/L (univariable: RR=6.49, 95%CI 3.16 to 13.30, P<0.001; multivariable-adjusted covariates: RR=6.15, 95%CI 2.66 to 14.3,P<0.001) with significant difference. No significant difference was found between patients with TC lower than 5.2 mmol/L and patients with TC higher than 6.2 mmol/L (univariable: RR=1.02, 95%CI 0.52 to 2.00,P=0.960; multivariable-adjusted covariates: RR=1.61, 95%CI 0.55 to 4.73, P=0.386). Gender-specific analysis showed for both male and female groups, the effective rates of patients with TC ranging from 5.2 mmol/L to 6.2 mmol/L were significantly higher than those of patients with TC lower than 5.2 mmol/L. There was no significant difference between patients with TC lower than 5.2 mmol/L and patients with TC higher than 6.2 mmol/L (P>0.05) in either male group or female group. Conclusion The current study suggests that patients with levels of TC ranging from 5.2 mmol/L to 6.2 mmol/L predicts the best prognosis.