[PROBLEMS] To reduce a sense of discomfort given to a driver due to vehicle deceleration caused by a downshift that is not intended by the driver, which is caused by a failure of a rotation speed sensor or the like.
[SOLUTIONS] An automatic transmission includes: a transmission mechanism configured to shift rotation of a driving source and transmit the rotation to a driving wheel; and a clutch configured to control transmission of a torque from the driving source to the driving wheel, wherein when a change rate of a rotation speed of the driving source is equal to or higher than a predetermined change rate, a torque transmission capacity of the clutch is reduced.