spherical lenses of ±1.0, ±2.0, ±3.0, ±4.0, ±5.0 and ±6.0 D were used on top of the trial frame with corrected condition as MPMVA (eyes-open with MPMVA). Under each induced-refractive error condition, general stability (ST) and sway power (SP) in frequencies by each subsystem were measured with Tetrax posturography with firm plates at patient's upright position, after performed the measurements under the conditions of eyes-open with MPMVA and eyes-closed. ST at eyes-closed was significantly greater than that at eyes-open with MPMVA (p < 0.001). ST was increased significantly for induced hyperopia of -1.0 D (p < 0.001) with decimal visual acuity of 1.07 ± 0.17 and for induced myopia of +3.0 D (p = 0.011) with decimal visual acuity of 0.16 ± 0.09, as compared to that at eyes-open with MPMVA. No significant difference was observed between induced hyperopia of -6.0 D and those at eyes-closed only. SP was increased significantly at low medium-frequencies of the peripheral vestibular signals in induced hyperopia, moreover, hyperopia induced at -6.0 D lenses was significantly different compared to that at eyes-open with MPMVA. Uncorrected low hyperopia in young subjects may lead to postural instability, although they can obtain clear vision. The corrected state of ametropia, especially hyperopia, is a more important factor of appropriate visual input in stable postural adjustment than visual acuity.