The invention is suitable for the technical field of optical communication and provides a hybrid optical fiber amplifier as well as a method and device for adjusting the gain and the gain slope of the amplifier. The hybrid optical fiber amplifier comprises an RFA (Raman fiber amplifier) and an EDFA (erbium doped fiber amplifier), wherein the EDFA excludes a variable attenuator; the RFA comprises a pump signal multiplexer, a pump laser group, an out-of-band narrow-band filter and a photoelectric detector; the EDFA comprises an input coupler, an erbium doped fiber, an output coupler, an input photoelectric detector and an output photoelectric detector, all of which are connected in sequence; and the hybrid optical fiber amplifier further comprises a control module for controlling the RFA and/or EDFA to adjust the gain and/or the gain slope according to an excepted amplification requirement. Due to the fact that the RFA and the EDFA are controlled and coordinated by the control module according to the technical scheme, an excepted amplification effect can be achieved; in addition, a series of problems caused by the variable attenuator can be avoided due to the fact that the EDFA excludes the variable attenuator.