To provide an automatic transmission for a vehicle miniaturized by efficiently disposing components.

This automatic transmission 10 changing speed by six speed gear stages dedicated to an FF (front engine and front drive) vehicle is provided with a first clutch 14 freely connecting/separating between a first planetary gear mechanism 13 and a second planetary gear mechanism 15, a second clutch 20 freely connecting/separating between an input shaft 12 and the second planetary gear mechanism 15, a counter shaft 18 having a driven gear geared with the drive gear and inputted with an output from the drive gear, and a differential shaft transmitting the output from the counter shaft 18 to an operation gear mechanism. This automatic transmission is characterized in that a parking gear 22 for locking the driving gear in parking is provided on the counter shaft and the parking gear 22 is disposed besides the second clutch 20 so as to position in an approximately same surface therewith orthogonal to the axis of the input shaft 12 and the counter shaft 18.