A planetary-gear-type multiple-step transmission including a stationary member, an input rotary member, an output rotary member, and first and second transmission units. The first transmission unit transmits a rotary motion from an input rotary member to the second transmission unit through first and second intermediate transmitting paths such that a speed of the rotary motion transmitted through the second intermediate transmitting path is lower than that of the rotary motion transmitted through the first intermediate transmitting path. The second transmission unit constitutes first, second, third, fourth and fifth rotary elements, each of which is provided by at least one of sun gears, carriers and ring gears of three planetary gear sets. The first rotary element is selectively connected to the second intermediate transmitting path, while being selectively connected to the stationary member. The second rotary element is selectively connected to the first intermediate transmitting path. The third rotary element is selectively connected to the first intermediate transmitting path, while being selectively connected to the stationary member. The fourth rotary element is connected to the output rotary member. The fifth rotary element is selectively connected to the second intermediate transmitting path.