PROBLEM TO BE SOLVED: To provide a composition for preventing and treating periodontal disease containing an extract from Nelumbo nucifera as an active ingredient, a composition for preventing and treating peri-implatitis, a cosmetic, and a preservative for an oral cavity cosmetic.SOLUTION: The present invention provides: a composition for preventing and treating periodontal disease containing an extract from Nelumbo nucifera as an active ingredient; a composition for preventing and treating peri-implatitis containing the extract from Nelumbo nucifera and Mucuna birdwoodiana as active ingredients; a cosmetic; and a preservative for an oral cavity cosmetic.