Abstract: This paper analyzes the frequency spectrum of typical vibration signal distribution and points out that the frequency spectrum of mass-spring oscillator vibration is consistent with the spectrum characteristics of quasi-periodic signal.So it no longer has the strict sense of the vibration cycle,only exists the approximate sense of quasi-periodic,and then the quasi-periodic concept of mass-spring oscillator is clarified.

Key words: spring oscillator, spring mass, simple harmonic oscillation, quasi-periodicity