Provided are a memory device and waveform data editing method and editing program thereof. Waveform data obtained by sampling a musical sound is acquired, and a difference between a harmonic frequency of an nth harmonic of the waveform data and a resonance sound frequency of the nth harmonic sound of a resonance sound generation circuit is calculated, and if the difference is 1 Hz or more, a waveform of a frequency component of 20 Hz centered on a central of the frequency of the nth harmonic of a frequency spectrum is clipped. The difference calculated in regard to the clipped waveform is reduced. The waveform and the clipped original waveform are combined to edit the waveform data. Thus, in the waveform data, the difference between the harmonic frequencies of the resonance characteristic is eliminated, and resonance is facilitated and occurrence of beat of the sound is prevented.