To simulate nonlinear propagation of a sound wave in any physical propagation substance inside a resonator.

In this method for simulating nonlinear propagation of a sound wave, a resonator is decomposed into continuous portions different in propagation-directional lengths, a law of linear propagation is applied in the vicinity of a boundary between the two portions, and nonlinear propagation of the sound wave including decomposition nonlinear and independentl of the first progressive wave and the second progressive wave propagated in a field of the sound wave is simulated for the respective continuous portions. A time- order equation over the whole propagation route to make possible connection for connecting a nonlinear propagation velocity to continuous samples of the sound wave entered into the respective portions, and calculation for calculating a sequence of the samples reaching to end part of a waveguide or the resonator with respect to different instants in the end parts of the each portion and the waveguide or the resonator, taking a sampling rate in an input into account is assigned to the continuous samples to be entered into the respective portions, as a function of a propagetion medium in the portions.