To provide an electrically-driven assist bicycle in which hindrance for performing start preparation is less even if it is dark in a bicycle-parking place.

A electrically-driven assist bicycle 1 assists on force for pressing down on a pedal 23 by a motor 40 driven by using a battery 41 as a power source. When a brake lever 32 is tightly grasped during a bicycle-parking state, a signal is transmitted from a brake detecting part 54 combined to the brake lever 32 to a control device 50, and the control device 50 makes a battery residual part 63 lighted in an operating part at hand 51 without waiting operation of the operating part at hand 51 itself. A user can recognize a position of a power switch 60 by using the lit battery residual part 63 as a key.