Because of the prominent advantages, diode lasers have a significant prospect of application. But limited by the beam quality, it is difficult to be a direct source applied in the fields demanding for power, beam quality and brightness at the same time. The technologies of beam shaping of 45° tilted cylindrical lens, self-polarization multiplexing and three-wavelength multiplexing are employed to couple 8 bars with three wavelengths into a laser beam, and a diode laser source is developed with continuous wave (CW) power of 500 W, electro-optical conversion efficiency of 39.5%, holistic beam quality of 12.44 mm·mrad and brightness of 42.8 MW/(cm2·sr), which can be applied directly in the fields of materials processing and defense.