Electrically assisted bicycle

An electrically assisted bicycle adapted to remarkably increase the running distance by effectively utilizing auxiliary power comprises an electric motor (1) changeable between a regenerative state and a nonregenerative state for generating electric power with the kinetic energy of the bicycle in the regenerative state to charge the battery (3) and interrupting the generation of power in the nonregenerative state, a speed detecting means (5) for detecting the running speed of the bicycle, and a control unit (13) for setting the motor (1) in the regenerative state when the running speed detected by the speed detecting means (5) is not lower than a predetermined value.