ENG(electronystagmography), one of the objective method analysing nystagmus, is capable of quantitative analysis of nystagmus as well as permanent storage of results. Furthermore, it has diagnostic value of measuring the velocity of nystagmus. It is generally accepted that each laboratory must establish normative data for their standard test protocol. In addition, these normative data should be categorized depending on the chronological change of human beings. This study was carried out in 80 healthy Korean subjects who were regarded as otoneurologically normal. They were classified into 4 groups based on their ages ; 10 to 19(group 1), 20 to 39(group 2), 40 to 59(group 3), and more than 60 years old(group 4). Each group was composed of 10 men and 10 women, respectively. All the subjects were tested for voluntary saccade, smooth pursuit, and optokinetic nystagmus, and their nystagmus was observed. The results were as follows : 1) Smooth pursuit were porformed at frequency of 0.2 Hz, with velocity of 20 deg(degree)/sec, 0.4 Hz, with 40 deg/sec, and 0.4 Hz with 20 deg/sec. Gain for them were from 0.70 to 0.92. 2) Saccade was tested using target velocity of 3-16 deg(degree) jump and 6-32 deg jump. Delay times were ranged from 162.4 ms(millisecond) to 212.6 ms and accuracies were from 72.4% to 92.1%. 3) Optokinetic nystagmus was tested with 3 different visual stimuli and directional preponderance were all within 20%. In the conclusion, morphoanatomic changes in CNS and vestibular system and their functional change are necessary to compromize the laboratory data. In the elderly group, we should consider the aging process as a essential factor to differentiate the validity of the results.