An electric bicycle configured in such a manner that, although the motor drive unit is mounted in the middle between the front wheel and the rear wheel, the loss of force during travel is reduced to a minimum and large shock and noise are prevented from being generated even if a recovery state is being selected during travel. The assisting-drive-force output sprocket (19) of a motor drive unit (20) is meshed with a drive force transmission chain for transmitting a pedaling force to the rear wheel. A damper (43) and an input/output changeover clutch (42) for changing the direction of force transmission are provided in the force transmission path between the motor output shaft (17a) of the motor drive unit (20) and the assisting-drive-force output shaft (41) thereof.
