A control device is applied to a vehicle including a steering device changing a tire angle in synchronization with a change in a steering angle while assisting in steering by driving an electric machine. The control device performs a steering support control for controlling a tire angle and a steering angle by driving the electric machine. The control device includes a control drive amount calculation unit calculating a control drive amount based on the target tire angle in a state where the steering support control is executed. The control device includes a steering drive amount calculation unit calculating a steering drive amount being a drive amount of the electric machine related to a steering torque. The control device includes a control unit that controls the electric machine based on the cooperative drive amount, during steering movement of the driver in a state where the steering support control is executed.