Human auditory sensitivity for the frequencies above 10KHz was examined with a new commercial ultra high frequency audiometer, Beltone 2000, in 80 male and 80 female normal hearing persons ranging in age from 4 to 79 years old. The purposes of this study were to determine the feasibility of ultra high frequency testing procedure routinely employed in clinical audiometry, to collect normative data using the procedure on various age groups, and finally to find the sensitive frequencies in each age group for early detections of ototoxic damage. It was noted that hearing thresholds were increased with frequencies and also with ages. The percent response to sound was decreased with increasing frequencies and ages. The approach described in the present study provided reliable thresholds and was found to be clinically feasible.