An asymmetrical phase-shifted distributed feedback fiber laser was ma de by phase mask plate moving method.In order to get higher power of laser output,the experiment of laser sign al self-amplifing was conducted respectively by forward pump structure and back ward pump structure using the same length erbium-doped fiber. The experiment results show that distributed feedback fiber lasers of the two se lf-amplifying structures can make full use of the pump laser power under the pr emise of the laser line width not broadening 23dB of laser signal power amplification is achieved at least.In contrast,forward pump amplification structure is more conducive to maintain the original laser signal noise characteristics.This paper provides a simple and feasible scheme for the distributed feedback fiber laser with larger output power.