A mounting device for mounting accessories on a handlebar of a bicycle includes a mounting frame and a plurality of sliding members. The mounting frame has a central hole and a plurality of coupling slots. The handlebar is inserted into the central hole of the frame member, and the coupling slots are provided on a surface of the mounting frame. The coupling slots each have an elongated direction, which is substantially parallel to an axial direction of the frame member, and the coupling slots are substantially parallel to each other. Accessories are connected to the sliding members respectively, and the sliding members each have a coupling portion to be detachably engaged in one of the coupling slots of the mounting frame.