An assembly of a light and a watch of a bicycle capable for adjusting angle comprises a mount and a light base. One side of the mount is mounted on the bicycle. A display screen is arranged at a top surface of the mount. A control member and a sensing member are arranged in the mount and electrically connected with the display screen. The sensing member is detected a variation of a rider and the bicycle to display on the display screen. One side of the light base is pivoted to a front end of the mount and the other end thereof has a light transparent portion. The light base is pivoted, rotated, and slid relative to the mount. The light base is electrically connected with the control member. The control member is for controlling a variation of a light beam of the light base. The mount is mounted on the bicycle so that the rider may see a display on the display screen and it is convenient to provide for lighting.
