A speed change device that includes a first clutch that includes a first piston, a first engagement oil chamber, and a first clutch drum that has a first outer tubular portion which extends in an axial direction and with which an outer peripheral portion of a first friction engagement plate is fitted, and a second clutch that includes a second piston, a second engagement oil chamber, and a second clutch drum that has a second inner tubular portion that extends in the axial direction and that slidably supports an inner peripheral portion of the second piston.