Abstract: A denture base separating material is disclosed, comprising an aqueous emulsion obtained by emulsion polymerization of methacrylic ester, acrylic ester, or acrylonitrile alone, or a mixed solution of two or more thereof, in the presence of a water-soluble radical polymerization initiator and a surfactant, the monomer composition of which is adjusted such that the minimum film-forming temperature is 23.degree. C. or lower having an appropriate adhesion and being able to be readily removed from the tissue conditioner, being easily confirmed at the time of application, being from dry spots and cracks on the denture surface, and not generating malodors.