To realize a setting angle adjusting device for a gyro sensor for detecting an azimuth capable of automatically adjusting the setting angle of the gyro sensor without confirming the installation angel of a vehicle navigation device body to various vehicles to manually adjust the setting angle to a horizontal angle.

In this setting angle adjusting device for gyro sensor 50 having a gyro sensor 1 for detecting an azimuth on a prescribed surface of a casing to set the detecting surface of the gyro sensor 1 to a horizontal reference, this device comprises a horizontal angle detecting means for detecting the angle difference between the detecting surface of the gyro sensor 1 and the horizontal reference A and a setting angle adjusting means for changing the setting angle of the gyro sensor 1 to the prescribed surface of the casing according to the angle detected by the horizontal angle detecting means.