The invention discloses a disturbance device for structural soft soil and a construction method of the disturbance device. The disturbance device comprises a transverse vibration plate, a connecting plate and a connecting sleeve, the connecting sleeve is installed at the lower end of a sleeve of a plastic drainage plate vibration plate insertion machine, the connecting plate is fixed to the connecting sleeve and is vertical to the axial direction of the connecting sleeve, the transverse vibration plate is rotationally connected to the end of the connecting plate, and a limiting plate is arranged above the connecting plate and fixed to the connecting sleeve. The disturbance device has the beneficial effects of being easy to construct and good in disturbance effect, and is suitable for disturbance drainage strengthening of the structural soft soil.