Provided are a control apparatus and a control method for a vehicle capable of automatically storing transmission control data corresponding to a transmission after the transmission is installed. The control apparatus for the vehicle includes a speed sensor for measuring the actual driving speed of a vehicle; a memory unit for storing first final reduction gear ratio data and second final reduction gear ratio data; and a control unit for setting a final reduction gear ratio corresponding to an installed transmission by comparing a difference between the actual driving speed of the vehicle received from the speed sensor and the driving speed of the vehicle calculated through a first final reduction gear ratio with a difference between the actual driving speed of the vehicle and the driving speed of the vehicle calculated through a second final reduction gear ratio.