Bithermal stimulation of the vestivular sense oragan was performed on 22 healthy young adults aged 25 to 33 year old without any previous otologic diseases to quantify normal vestibular responses. Life Tech electronystagmography instrument unit was used to record latency, duration, amplitude and speed of slow component(SSC). Relative values of unilateral weakness(UW) was 22.7%, and directional preponderance(DP) was 22.0% by maximum SSC. Relative values of UW was 19.9%, and DP was 21.7% by maximum total amplitude(MTA). Culminative values of maximal SSC and those of amplitude were more reliable than maximal SSC and MTA. Latency or duration of the nystagmus showed marked difference between both ears. In contrary, amplitude or SSC were more reliable parameters to test UW or DP than latency or duration of the nystagmus. In testing SSC and amplitude warm stimulus was more stronger than cold stimulus.