High peak power, high stability laser beams with excellent beam quality are ideal choices for material manufacturing and processing. A semiconductor laser with repetition frequency of 120 kHz, pulse width of 220 ps, average power of 26 μW is used as seed source. The pre-amplifier consists of two fiber amplifiers. The power amplifier consists of four stages end-pumped Nd:YVO4 solid amplifiers. The average power of final laser output is up to 39.2 W with peak power of 1.5 MW. By optimizing the crystal doping concentration, crystal temperature, the pump beam diameter and beam filling factor in each solid amplifier, the output beam with M2 factor of 1.3 is achieved.