An automatic transmission is provided, which includes a brake including a hub member which is coupled to a transmission case and includes first and second hub members, a drum member coupled to a given rotary member, friction plates, a piston configured to engage the friction plates, and a valve body disposed in a lower part of the transmission case. The first hub member includes a radially outer circumferential part formed with a first spline part spline-engaged with the transmission case, and a cylindrical part provided at a radially inner circumferential side and formed with a second spline part with which the friction plates are spline-engaged. The second hub member is disposed at a side part of the first hub member, is provided by fitting a radially outer circumferential part of the second hub member to the transmission case, and has a feed part for lubrication.