The present invention discloses a harmonic peak-free vibration isolator and a damping module thereof. The harmonic peak-free vibration isolator is composed of a vibration damping module, a damping module, and a linking module. The vibration damping module comprises a hollow internal-thread hexagon bolt, an adjusting gasket, an internal-thread sleeve, and a main spring. The damping module comprises a stepped damping sleeve, a first damper, and a second damper. The linking module comprises an upper end cover, a lower end cover having a cylindrical projection, and a base. The stepped damping sleeve is fastened in the cavity of the vibration isolator by means of the internal-thread hexagon bolt and the adjusting gasket. The damping module in the harmonic peak-free vibration isolator is relatively simple in implementation structure; during vertical vibration of the vibration isolator, two dampers in the damping module may contact with two concave connections to provide stable damping forces in the vertical and horizontal directions, thereby achieving a good centering return effect on transverse vibration; and the vibration isolator has a strong resonant depression effect.