Abstract: Based on the advantages of diode laser, such as high efficiency and high integration, blue diode laser source can be widely used in highly-reflective and highly conductive materials processing. This paper introduces a high power high brightness blue diode laser fiber coupling module based on 3×9 single emitter diode laser array, which can realize 75 W single polarization 450 nm diode laser output from 100 μm 0.2 NA fiber. Polarization beam combining can also be used to further improve the fiber coupling blue diode laser power.