PROBLEM TO BE SOLVED: To provide a sleep quality improver useful for improving the quality of sleep and a parasympathetic activity enhancer useful for enhancing parasympathetic activity.SOLUTION: A sleep quality improver has rosmarinic acid, a glycoside thereof or a salt thereof as an active ingredient, and extends a non-rapid eye movement sleep duration.SELECTED DRAWING: NoneCOPYRIGHT: (C)2020,JPO&INPIT【課題】睡眠の質の改善に有用な睡眠の質改善剤及び副交感神経活動の亢進に有用な副交感神経活動亢進剤の提供。【解決手段】ロズマリン酸若しくはその配糖体又はそれらの塩を有効成分とし、ノンレム睡眠持続時間を延長する、睡眠の質改善剤。【選択図】なし