Abstract: The present invention relates to a battery-integrated driver for an electric bicycle, and more specifically, related to a driver capable of changing an ordinary bicycle to an electric bicycle. The driver is installed in a hub on the back of a general bicycle and can be housed inside the hub without an external power connection. Thus, a user can easily assemble an electric bicycle and use it conveniently. The battery-integrated driver includes: a wheel hub (H); a rear side chain support (C) and a saddle support (S) of a bicycle which are coupled to each other at the wheel hub (H); a hub (30) provided in the wheel hub (H) and coupled to a wheel rim through spokes, wherein a tire is installed on the wheel rim; a driver (A) provided in the hub (30) and including an electric motor (660), wherein the electric motor (660) supplies electric power to rotate a wheel; and a battery provided in the driver (A) in a detachable manner and driving the electric motor (660).