A powertrain for a vehicle may include a power source, a left motor/generator and a right motor/generator, a left planetary gear set and a right planetary gear set each having a first rotary member connected to the power source, a second rotary member connected to driving wheels, and a third rotary member connected to either the left motor generator or the right motor generator, a brake configured to limit rotation of the first rotary member of each of the left planetary gear set and the right planetary gear set, a left clutch selectively connecting or disconnecting the second rotary member and the third rotary member of the left planetary gear set to or from each other, and a right clutch selectively connecting or disconnecting the second rotary member and the third rotary member of the right planetary gear set to or from each other.