The present invention aims to provide ananti-norovirus agent that has high norovirus-inactivatingactivity and is safe for the human body, and ananti-norovirus composition that contains the anti-norovirus agentand is useful for disinfection and infection control againstthe norovirus. An anti-norovirus agent according to thepresent invention is characterized by containing, as anactive ingredient, an extract from a plant of the genusDiospyros containing tannin (hereinafter referred to as a"persimmon extract"), preferably a persimmon extractproduced by heating squeezed juice or an extract from thefruit of a plant of the genus Diospyros or treating thesqueezed juice or the extract with an alcohol. Ananti-norovirus composition according to the present invention ischaracterized by containing the anti-norovirus agent and atleast one selected from the group consisting of alcohols,surfactants, antimicrobial agents, humectants, and cosmeticfats and oils, and preferably further containing an organicacid, such as citric acid, and/or a salt thereof or vitaminC.
