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A method for the diagnosis of labyrinthine hydrops is proposed that takes advantage of specific physiological features of internal ear functioning. Namely, the basal membrane of the inner ear exposed to a low-frequency tone undergoes synchronous sinusoidal oscillations along its entire length; simultaneously, sensitivity of the organ of Corti changes periodically. Under normal conditions, perception of 1,000 Hz tonal signals at the background of a low-frequency masker varied substantially depending on the phase during which the signal came. In the maximum discharging phase that corresponded to a 270 degree deviation of the basal membrane from its initial position, it was maximally displaced towards the vestibule staircase, and perception of the test tone was most affected. Patients with hydrops of the internal ear exhibited phase-independent constant perception of high-frequency tonal signals against the background test tone. It is concluded that the method of phase audiometry can be used in large research centres for the comprehensive evaluation of cochlear-vestibular function during hydrops formation.