The present invention discloses an optical fiber display screen and a preparing method thereof. The invention is characterized in that the screen body is composed of an outer frame of the display screen and a casing. The casing is composed of a plurality of casing units, and each casing unit is composed of a plurality of module units, side boards of the casing, a fastening connecting rod and a connector. The module unit is composed of a clip, a lens and a buckle. The preparing method is that the optical fibers at projection end of ten thousands of optical fibers and the auxiliary device are fastened to a total bundle end surface with methods of veneering and baking. Each screen installation module unit uses the methods of veneering and auxiliary device to make the projection end to a module bundle end. The same method is used for preparing a casing bundle end. Finally the casing bundle end is accumulated to a total bundle end surface of screen. The total bundle end surface at the projection end is prepared with the methods of veneering and auxiliary device. Furthermore the total bundle surface at the projection end is grinded and polished to form a surface. The optical fiber display screen according to the invention has advantages of high brightness, high resolution, lifelike color, wide visual angle, strong convertibility, low energy consumption, strong hostile environment resistance, long service lifetime, convenient assemblage, low maintenance cost, multiple forms of connecting signals and the like.