A continuously variable transmission includes a variator capable of varying a speed ratio continuously, and a subtransmission mechanism provided in series with the variator. On the basis of an operating condition of a vehicle, a transmission controller sets a destination through speed ratio, which is an overall speed ratio of the variator and the subtransmission mechanism to be realized in accordance with the operating condition, and controls the variator and the subtransmission mechanism on the basis thereof. When shifts are prohibited in the subtransmission mechanism, the destination through speed ratio is limited to a speed ratio range that can be realized only by a shift in the variator.