In a shift control method, when a speed ratio of an automatic transmission is shifted from a third speed ratio to a first speed ratio before stoppage of a vehicle, a down shift line 3-1 in a shift pattern is shifted to a high-speed side to initiate shifting under a power-OFF condition. A third brake is released by setting the duty ratio of an electromagnetic valve of the third brake at 0% to establish a free condition (neutral condition) in an output shaft of a second transmission. While the duty ratio of an electromagnetic valve of a second clutch in a first transmission mechanism is set at 0%, the duty ratio of an electromagnetic valve of a second brake is gradually increased, so that the shifting from the second clutch to the second brake is made, and the first transmission mechanism is operatively shifted from the third speed ratio to a speed ratio corresponding to the first speed ratio. Then, the third brake is engaged again upon completion of the shifting and after mechanical engagement of a one-way clutch. Consequently, it is possible to reduce shocks in shifting the speed of the vehicle.