An optical gain of 22 dB at 1.535 μm is obtained in an Er3+- doped fibre amplifier for a total pump power of 54 mW. The Er3+ doping concentration is 34 ppm, and the pumping source is GaAlAs laser diodes at 820 nm. By using an Er3+ fibre with a doping concentration of 390 ppm, the maximum gain is as high as 29.4 dB for a pump power of 83 mW.