To provide an operating device control device for obtaining information about a rotational angle of an operating device, while reducing the influence due to an individual difference and/or variation of a reference sensor signal in accordance with a sensor signal output from the gyro sensor mounted in the operating device. A control device of an operating device having a gyro sensor for detecting an angular velocity and outputting a sensor signal in accordance with the detected angular velocity, the control device obtains an output signal from signal output means for outputting an output signal in accordance with a difference between the sensor signal output from the gyro sensor and a predetermined reference signal, then estimates a reference sensor signal to be output by the gyro sensor when no angular velocity is detected, based on the output signal, and changes the predetermined reference signal according to the estimated reference sensor signal.