熊果素（Arbutin，C₁₂H₁₆O₇），亦作熊果苷，是一种由杜鹃花科植物熊果叶中萃取出的成份，在梨、小麦等植物中也有发现，因为能抑制酪氨酸酶（tyrosinase）的活性，进而阻碍黑色素的形成，对美白颇具功效，因而被用于化粧及保养品中。熊果素也有利尿与尿路杀菌的功用，所以也被用于尿路消毒药中。

熊果素有α和β两型，α型对酪氨酸酶活性的抑制力比β型强约10倍。虽然熊果素具有美白功效，但用量不当反而可能促进黑色素的生成。

****于2001年6月5日公告美白用的熊果素添加限量为7%。

Arbutin is a glycoside; a glycosylated hydroquinone extracted from the bearberry plant in the genus Arctostaphylos. It inhibits tyrosinase and thus prevents the formation of melanin. Arbutin is therefore used as a skin-lightening agent. Arbutin is found in wheat, and is concentrated in pear skins. It is also found in Bergenia crassifolia. Arbutin was also produced by an in vitro culture of Schisandra chinensis.