The invention relates to a preparation method and application of a novel graphene foam rectifying tower filler. At a high temperature, through a solvothermal way, a graphene oxide solution is subjected to molding; a metal frame structure is embedded in a process; thus, one rectifying tower filler unit is formed; a porous structure of the rectifying tower filler unit can be used as a microreactor for catalytic rectification. A novel three-dimensional graphene filler is compared with HY-Pac and Pall ring fillers, and is used for filling a rectifying tower; a graphene filler maintains a regular filler property to a great extent; the mass transfer capacity is high; the graphene filler is large in liquid holdup, and can be used as a novel catalytic microreactor; the pressure drop of the graphene filler can be decreased to 1/3 of that of a conventional filler.