Objective：To investigate the necessity of treatment for sudden deafness and the influencing factors for its prognosis. Methods：Totally 498 cases（526 ears） with sudden deafness from February 2011 to May 2013 were retrospectively analyzed. The pa－tients were divided into 4 types according to their audiometric curve：type A was acute sensorineural hearing loss（SNHL） in low tone frequencies，type B was acute SNHL in high tone frequencies，type C was acute SNHL in all frequencies（PTA≤80 dB HL） and type D was profound SNHL in all frequencies（PTA≥81 dB HL）. The patients were treated with different regimens based on their hearing types. The therapeutic effect and prognostic factors were analyzed. Results：All patients（526 ears） were recruited and the ratio of male to female was 0.95∶1. The average age was （45.39±15.78） years old. 91 ears were type A（17.30%），74 ears were type B（14.07%），191 ears were type C（36.31%），and 170 ears were type D（32.32%）. The therapeutic effects of different types were analyzed. The ef－fective rate was 70.33% in type A，50.26% in type C，51.76% in type D，and 35.14% in type B. The multivariate logistic analysis showed that age（OR=0.977，95%CI=0.965 to 0.989，P=0.000），the type of audiometric curve（OR=0.977，95%CI=0.180 to 0.748，0.372 to 1.199，0.300 to 0.963，P=0.035），the affected ear side（OR=0.977，95%CI=0.450 to 0.989，0.161 to 0.628，P=0.002），interval from onset to intervention（OR=0.977，95%CI=0.925 to 0.967，P=0.000） were 4 independent risk factors correlated to therapeutic effect of sudden deafness. Conclusion：The curative effect of sudden deafness is closely related to the age，the type of audiometric curve，the affected ear side，interval from onset to intervention，and hypertension. Different types of sudden deafness have different curing effects. The curative effect for the type in low tone frequencies is the best，followed by the type of profound SNHL in all fre－quencies and acute SNHL in all frequencies. The result of the type in high tone frequencies is the poorest. It’s important to treat patients with sudden deafness with differential regimens based on the types of audiometric curves.