To provide a vehicular power train including at least two drive sources 4, 6 and a twin clutch type automatic transmission 7 which is capable of performing the replaceable motion of the twin clutch 21, 22 type automatic transmission 7 without any coupling shock rapidly as much as possible.

In the vehicular power train, any one of a power transmission path for odd stages for transmitting the rotational power of one drive source 6 to a transmission output shaft 3 by replaceably controling an odd-stage clutch 21 and even-stage cluutch 22 and further odd group speed change gear trains 31, 33, and a power transmission path for even stages for transmitting the rotational power of the other drive source 4 to the transmission output shaft 3 via an even stage clutch 22 and even group speed change gear trains 32, 34 is formed.