Pure tone audiometry and Brainstem evoked response audiometry(BERA) were compared in 29 ears with conductive hearing loss ; 15 of them were adults with chronic otitis media and 14 of them were 4 to 9 year old children with middle ear effusion. Three methods were used to predict conductive hearing loss ; 1) comparison of sound pressure levels that reveal same latency of wave V, 2) comparison of latency periods of wave V in a given sound pressure level, 3) detection thresholds level of wave V. The predictions from these relationship were quite promising. The results suggests that BERA can be a valuable tool for detecting and predicting the presence of conductive hearing loss in chronic otitis media and middle ear effusion especially in young children when conventional pure tone audiometry was difficult to perform.