To provide a dynamo-electric type vibration testing device capable of reducing an interaction between a testing object and an testing object mounting part.

A control part 141 executes external force calculation control for calculating an external force df taken into consideration with the interaction of the testing object mounted on the testing object mounting part with respect to the testing object mounting part, and a modeling error based on a damping coefficient Cd of a damper and an elastic modulus Kd of a spring. The dynamo-electric type vibration testing device executes external force calculation processing, using a displacement amount xs of the testing object mounting part obtained from a displacement sensor 131, an acceleration value (d2xs/dt2) obtained from an acceleration sensor 133, and a current value I of a driving coil 125 obtained from an ammeter 135.