The percentage of patients with bilateral canal paresis (CP) was 12.9% in the 279 patients suffering from dizziness or vertigo visiting the Laboratory of Equilibrium Function at Kumamoto University hospital from 2002 to 2006 who were enrolled in the study. As the cause of bilateral CP, Meniere's disease and central nervous system diseases were considered to be the most important. We divided patients with bilateral canal paresis into the light CP group and severe CP group and examined the differences in the between the two groups. The body equilibrium was affected to a more severe degree in the severe CP group as compared with that in the light CP group. On the other hand, the result of ADL evaluation showed the absence of any significant difference between the two groups. As long as the semicircular canal function was maintained, the body equilibrium was maintained. We thought that the correspondence that did not let light CP shift to severe CP is necessary.