A new two-stage L-band erbium doped fiber amplifier (EDFA) structure with a single fiber grating is introduced to solve the problem of poor power conversion efficiency of a conventional L-band EDFA. A mid-way isolator is used in the structure to improve the noise figure. The fiber grating is used to reflect the wasted C-band backward amplified spontaneous emission (ASE). The influence of the pump power ratio and the Bragg wavelength to the characteristics of this EDFA is studied experimentally. For such an EDFA structure with a pump power of 70 mW, 22.26 dB gain and 4.96 dB noise figure is obtained for a 1570 nm signal with an input power of-30 dBm.