The present invention provides an excellent moisturizing agent, which includes the following components (A) and (B): (A) a sugar fermentation product generated by using a yeast belonging to Kluyveromyces； and (B) a polyhydric alcohol having a specific gravity of above 1.02 at 20 DEG C, which can be selected from at least one of the glycerol, propanediol, propylene glycol, and dipropylene glycol. In the moisturizing agent of this invention, the dry solid content of component (A) can be set to be above 0.0001 mass% and below 0.09 mass%. Furthermore, the ratio of the dry solid content of component (A) to the content of component (B) can be set to be 0.0000025-0.9:1.提供優良之保濕劑。提供一種保濕劑，其中含有以下成分(A)及(B)；(A)為由克魯維酵母(Kluyveromyces)屬之酵母產生的糖發酵物，(B)為於20℃之比重為1.02以上的多元醇。在本發明相關之保濕劑中，前述成分(A)之乾燥固形分的含量，可設定為0.0001質量%以上0.09質量%以下。又，前述成分(A)之乾燥固形分與前述成分(B)之含量比率，可設定為0.0000025~0.9：1。
