A bicycle operating device comprises a base member, an operating member, and a hydraulic unit. The base member comprises a first end portion, a second end portion, and a gripping portion. The gripping portion is provided between the first end portion and the second end portion. The operating member is movably mounted to the base member from a rest position toward an operated position. The hydraulic unit is provided at one of the base member and the operating member. The hydraulic unit comprises a hydraulic cylinder and a piston. The hydraulic cylinder includes a cylinder bore. The piston is arranged in the cylinder bore. The piston is configured to be pulled from an initial position to an actuated position in response to a movement of the operating member from the rest position toward the operated position to supply a hydraulic pressure toward at least one bicycle component.