Provided are a method for realizing precise gain control for a hybrid fibre amplifier, and a hybrid fibre amplifier. A method for firstly outputting a constant power by means of an erbium-doped fibre amplifier is used, thus, a comparable source signal optical power is provided for a raman fibre amplifier of a next stage, and by means of comparison between the source signal optical power calculated after starting pumping of the raman fibre amplifier and the source signal optical power detected while turning off pumping, a feedback for gain control is formed, and gain control precision of the raman fibre amplifier is improved greatly. Moreover, erbium-doped fibre amplifier parts of all the hybrid fibre amplifiers simultaneously output a constant optical power, and raman amplifier parts of all the hybrid fibre amplifiers simultaneously start calibration, so that the time for starting the whole system operation is advanced greatly. There is no limitation as to whether an erbium-doped fibre amplifier part uses a built-in variable attenuator or not, and a gain adjustment range of the hybrid fibre amplifier is increased greatly.