An optical amplification fiber for an optical fiber amplifier that amplifies a signal light using a pumping light has an absorption coefficient that satisfies conditional relations .alpha.s.gtoreq.2.0 dB/m and .alpha.p/.alpha.s.gtoreq.-0.0697.times..alpha.s+1.30, where .alpha.p is the absorption coefficient in a pumping light wavelength band, and .alpha.s is the absorption coefficient in a signal light wavelength band.

 
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