The advent of rotation test and computed dynamic posturography(CDP), along with the existing electronystagmography(ENG) has endowed the physician with an amazing insight into the pathophysiology of the vestibular system and a credible tool for the diagnosis and monitoring of dizzy patients. In the past caloric test was a sole modality to evaluate the vestibular function of the patients with peripheral vestibulopathy in spite of its great variability and non-physiologic stimulation. Up to this time we do not know all the findings of rotation test and CDP, but it is generally accepted that the cause of dizziness could be understood more clearly using these machines. We have investigated the results of the three vestibular function tests to clarify the patterns of the results in unilateral peripheral vestibulopathy patients and to confirm the usefulness of each test. Thirty-four dizzy patients with unilateral peripheral vestibulopathies underwent rotation chair test, CDP, and ENG including cool monothermal caloric test. Caloric test was performed using 17℃ tap water. The slow harmonic acceleration(SHA) rotation test was undertaken at the frequency range of 0.01 to 0.32 Hz. Sensory organization test of CDP was carried out and sensory analysis was analyzed. The rotation test was more sensitive(91%) than the caloric test(79%) and CDP(77%) in showing abnormalities. Among the various rotation tests, the decrease of gain in low frequency was the most frequent finding(65%) followed by increase in phase lead(56%), asymmetry(53%), and decrease of gain in all frequencies(18%). Ten of 11 patients who showed obscure clue in caloric test were confirmed to have unilateral peripheral vestibulopathy by rotation chair test. And 2 of 3 patients who showed normal responses at the rotation tests showed canal paresis in caloric test. This study demonstrates the usefulness of caloric test, rotation test, and posturograhy in diagnosing unilateral vestibular disorders, and presents various patterns of each test in unilateral peripheral vestibulopathy.