PURPOSE: To obtain excellent damping characteristics without providing any displacement sensor.

CONSTITUTION: The vibration controller is equipped with an electromagnet 1 which is arranged opposite a machine vibration body M across a specific gap. a power amplifier 2 which excites this electromagnet 1, a current detector 6 which detects the coil current that the power amplifier 2 supplies and outputs a 1st detection signal corresponding to it, a magnetic flux detector 7 which detects the magnetic flux produced at the magnetic part of the electromagnet 1 and outputs a 2nd detection signal corresponding to it, a displacement unit 8 which estimates the vibration displacement of the vibration body 1 from those 1st and 2nd detection signals and outputs a displacement estimation signal corresponding to the estimation result, and a controller 4 which generates a control signal obtained by performing PD operation, etc., for this displacement estimation signal and feeds the control signal back to the power amplifier 2.