To provide a power generating damper device capable of generating high damping force in spite of an operation state of a vehicle, and capable of attaining energy saving.

This power generating damper device for damping vibration by operating a generator 1 by a transmission mechanism 100 and regenerating displacement energy to electrical energy comprises a generator 1 for generating power by relative movement of a magnetic field energized by a field winding to an armature winding, the transmission mechanism 100 which relatively moves the magnetic field and the armature winding by the displacement energy stored a suspension device KS by the displacement of a wheel, a state detecting sensor 16 for detecting the operation state of the vehicle, an excitation power supply 17 for energizing and exciting to the field winding so that the magnetic field varies for the armature winding, and a control unit 18 for controlling the driving of the excitation power supply 17 so as to increase a damping force to the relative movement of the magnetic field to the armature winding.