This Paper reports the result of changes of blood rhloogy in 55 casesof sudden deaf patients over 40 years oldCompared with the normal
it showed the result except the whole blood Viscosity was significantly different(P<0.01).Comared with the effect
the changes of hemorhology were significantly different(P<0.05).So weconclude that the elevated blood viscosity is one of the causes of sudden deaf patients who is over 40 years old.