Conventional audiometry can be checked up to only 60-100 dB, so author have been rechecking with auditory booster of 25 dB in the scale-out cases by conventional audiometry, and summarized the auditroy result in 130 cases(166 ears) by exact audiometry using auditory booster in last three years. 1) The ratio of male and female was 7：2 and second decade was most as 46.9%. 2) Right side was 36.9%, left was 35.4% and both was 27.7%. 3) The onset of hearing loss was below 10 years old in 43.4% and above 10 years in 56.6%. And the time of initial examination was below 10 years old in 28.3% and above 10 years old 71.7%. The duration from onset to initial examination was longer in male than female. 4) The most cause of scale-out hearing loss was head trauma as 18.6% and next was unknown fever, congenital, familial and ear trauma in order. Unknown cause was about 17.9% and especially, there was middle ear operation in 3.4%. 5) Scale out was more in high frequency than in lower or middle frequency and this was also same in rechecking using auditory booster. These results were remarkable in head trauma cases. 6) In head trauma, noise trauma and chronic otitis media cases, opposite hearing was normal or mild deafness but unknown fever, congenital, familial, viral infection, drug-intoxication and sudden deafness cases had moderate-severe or more opposite hearing. 7) Accompany symptoms were tinnitus 28.5%, dizziness or vertigo 18.5%, headache 6.9%, earache 6.9% and ear fullness 2.8%.