A wideband highly linear amplifier includes a plurality of pre-distortion units for respectively linearizing digital signals of a plurality of bands, a synthesis unit for synthesizing output signals of the pre-distortion units, a single amplifier for amplifying signals outputted from the synthesis unit, distribution units for respectively separating the signals for each of the plurality of bands from the output signals of the amplifier, a plurality of inverse compensation attenuators for respectively attenuating the separated signals for each of the plurality of bands, and a feedback path for respectively feeding the attenuated signals for each of the plurality of bands back into the pre-distortion unit of the corresponding band out of the plurality of the pre-distortion units.