Otoacoustic emission (OAE) originated from very specific locations in the cochlea are closely linked to the function of outer hair cells. Thus, the latency and amplitude of distortion product otoacoustic emission (DPOAE), afford valuable information about cochlear processes such as study of traveling wave propagation. This study was to predetermine the discrimination standard point of DPOAE latency, which discriminates the degree of age, and to estimate the accuracy and predictability of the discrimination standard point of DPOAE latency. DPOAE latency was examined in series of human subjects, with clinically normal hearing, ranging in age from 20 to 69 years. All 60 subjects were divided into 5 age groups. The aging effect on pure tone audiometry (PTA) did not exist, especially 60 years group showed higher threshold in all frequencies. The gender effect on DPOAE latency did not exist. The DPOAE latency increased as the frequency increased and decreased as the age increased. This finding was that, when compared between emissions in each age DPOAE latency were able to detect the functional effects of auditory aging. KEY WORDS：DPOAE·DPOAE latency·SOAE·TEOAE.