To control a transmission ratio variable device accurately after releasing the locking of a lock device even when a steering wheel is turned while the lock device is in a lock-on state.

A steering control device for a vehicle includes the transmission ratio variable device 20, which changes a transmission ratio by relatively rotating an output shaft 18 to an input shaft 16 by an electric motor 26, a rotation angle sensor 72, which detects an rotation angle of the motor 26 and outputs output signals regarding the range of a preset reference rotation angle as that of one cycle, and a rotation transmission restricting mechanism 33, which restricts the rotation angle of the motor 26 at the time when a steering wheel 12 is turned over the maximum turnable range while the lock device 56 is in the lock-on state for suppressing the change of the transmission ratio. A variable range of the rotation angle of the motor 26 in the lock-on state is estimated and a current rotation angle of the motor 26 is estimated based on the output signals of the sensor 72 and the estimated variable range of the rotation angle.