An all fiber structure nanosecond pulse is realized through two stage amplifiers, which has 8.78 W in average power, 1 064 nm in wavelength, 11 kHz in repetition frequency, 125 ns in impulse duration, 0.8 mJ in single pulse power, 5.3 kW in peak power. The optic-optic conversion efficiency is 55.6%. Meanwhile, we setup another system, a nanosecond pulse is realized through just one stage amplifier, which has 10.10 W in average power, 1 064 nm in wavelength, 11 kHz in repetition frequency, 150 ns in impulse duration, 0.92 mJ in single pulse power, 6 kW in peak power. The optic-optic conversion efficiency is 67%. The only one stage of amplifier simplifies the system structure and reduces the cost.