A medium processing apparatus includes a conveying unit, a liquid applier, a crimper, a liquid-applier pivot mechanism and a crimper pivot mechanism. The conveying unit conveys a medium in a conveyance direction. The liquid applier applies liquid to the medium conveyed by the conveying unit. The crimper presses and deforms a plurality of media including the medium to which the liquid is applied by the liquid applier, to bind the plurality of media. The liquid-applier pivot mechanism pivots the liquid applier about a pivot extending in a thickness direction of the medium. The crimper pivot mechanism pivots the crimper about another pivot extending in the thickness direction of the medium.