Ninety eight cases with functional deaf who visited in recent 13 years were studied. The results were as follows; 1) Patients were likely to increase in the last 10 years. 2) Females seemed to be more frequently suffered from functional deafness rather than males. 3) It was found that there were two peaks of age when patient had functional deafness. 4) Chief complaints in most cases were hearing loss. 5) Pure tone audiograms in these cases showed bilateral in most cases, symmetrical curve, sensorineural in type, flat and sloping in shape (including saucer type), and its hearing level revealed in 30-40dB in most cases. 6) Békésy audiometry was useful for diagnosis. Ninety cases out of 98 showed the V type of Jerger classification. 7) Psychological problems related to troubles of school and friends were observed as causative factors, and episodes concerned otological problems were found to be as triggers. 8) It is possible to make sure a diagnosis by using ABR. For diagnosis, however, it was necessary to doubt the presence of this disease, and then it was important to find out the discrepancy in a battery of hearing test. 9) In some cases, the exactly the same, but higher threshold levels for hearing are always detected in repeated examinations of their audiograms, suggesting the actual disturbance of the loudness recognition in these patients.