The precise machining system of UV picosecond laser is a sort of machine applied in the fields of mechanical, basic subjects of engineering and technology science, materials science, and mechanical engineering. Owing to the development of the picosecond fundamental frequency laser of high beam quality and high power, the power of the UV picosecond laser has reached the level of 50W and the output records are constantly being broken. The continuously improved property of new nonlinear crystals has made great contributions to the stability and working lifetime of high-power UV picosecond laser.