For the technical requirements of large energy multi-band picosecond laser,the regenerative amplification technology of new non-independent radio modules is proposed,laser damage resistance technology,efficient frequency doubling,sum frequency and quadruplicated frequency technology of large energy laser amplifier system were researched and analyzed under high power density. When the repetition frequency is 10 Hz,the output pulse energy of 1064 μm is 239.8 mJ,magnification reaches to 108 times,the peak power density is above 40 GW/cm2.