As like the other leisure sports, the populations enjoying SCUBA diving are much increasing these days. Though not the most serious but the most common medical problems from SCUBA diving is related to the ENT field especially to the ears. To provide essential medical knowledge to the SCUBA divers for safe-diving and to provide essential diving knowledge to the ENT Drs. for better diagnosis and treatment of the problem divers, author conducted a clinical observations in 12 cases of otologic barotraumas from SCUBA diving at Yeungnam University Hospital from August 1988 to October 1993 and reviewed to the latest literatures about otologic barotrauma including concepts of underwater physics and physiology and cause, mechanism, symptom and treatment of the external, middle and inner ear barotrauma. Sex ratio of male to female was 11 : 1 and age distribution ranged from 22 to 42 years old, the highest in the thirties(58.3%). In regard to diving carrier, half of the cases occurred during the diving education(50%) followed by 25% of the cases occured below 1 year of diving carrier, showing the shorter diving carrier, the higher incidence of barotrauma. In regard to the depth of barotraumatized water, 50% of cases occurred within 5m water followed by 16.7% within 10-19m water. As predisposing factors, 7 cases(58.3%) combined URI followed by 5 cases(41.7%) of uncontrolled descent. Otoscopic findings showed abnormal findings only in tympanic membrane in 5 cases(41.7%), perfortion in 4 cases(33.3%) and otitis media with effusion in 3 cases(25%). Hearing threshold ranged 22-45dB(ISO) and 11 cases(91.7%) showed hearing loss of average threshold 35.8dB(ISO).