Because of the large difference in beam quality between the fast axis and slow axis directions of the diode laser, a prism stack is used for beam shaping to complete fiber coupling of the diode laser stack. A beam shaping technology of filling the dark areas in the fast axis direction before rotating rearrangement is proposed. The technology is based on the total internal reflection of prism stack and the deviation effect of the parallel plate, and it can complete the whole beam shaping process without using prism stack. By the proposed technology, the laser from stack which is equipped with 8 bars is coupled into a fiber with a core diameter of 200 μm and numerical aperture of 0.22. The output power can reach 544.47 W and optical-to-optical conversion efficiency of the system can reach up to 85%.