The recent progress of the high power pulse double cladding fiber lasers are reviewed, the simulation calculation for pulse sharp amplified by the double cladding fiber is obtained by using small signal instantaneous gain model. The key points of the master-oscillator fiber power amplifier (MOPA) are analysied in detail. The system can emits average power up to 133.8 W at the wavelength of 1064 nm and repetition rate of 100 kHz.