In this paper experimental results on the pulse amplification using Yb doped fiber amplifier were given, gain over 26 dB was obtained on 18 m Yb-doped fiber, and the single mode LD laser at 1.053 μm was used as the injected signal modifying with repeat rate at 1 kHz and the pulses vary with 1 μs, 2 μs. 5 μs, 10 μs. The results of the relationship between the gain and the pump power and other relative relationship, show that the gain is sensitive about the pump power, the length of fiber, and also about the signal's power, and with small signal amplification, the output pulses have not been distorted this show the equipment can be used as the front end of the huge pulse energy laser.