This research proposes reduction in the amplitude of nonlinear oscillation in a high-Tc superconducting magnetic levitation system by using a vibration absorber. High-Tc superconducting levitation systems have very low damping and stable levitation without control. However in such low-damped systems, complicated phenomena of dynamics can be easily generated by nonlinearity of the magnetic force. Our previous research showed that, when the frequency of vertical excitation is in the neighborhood of double the natural frequency in the horizontal direction, horizontal oscillation can occur parametrically through nonlinear coupling between vertical motion and horizontal motion. This research discusses on effect of a vibration absorber on a parametrically excited horizontal oscillation of the levitated body. The numerical results showed reduction in the amplitude of the horizontal oscillation. This kind of vibration absorber can be useful for reducing the amplitude of the autoparametric resonance of a high-Tc superconducting levitation system.