Amazake is a traditional sweet, low-alcohol or non-alcoholic Japanese drink made from fermented rice. Amazake dates from the Kofun period, and it is mentioned in the Nihon Shoki. It is part of the family of traditional Japanese foods made using the koji mold Aspergillus oryzae , which also includes miso, soy sauce, and sake.

Aspergillus oryzae is a mold used in East Asia to saccharify rice, sweet potato, and barley in the making of alcoholic beverages such as sake and shōchū, and also to ferment soybeans for making soy sauce and miso. It is one of the different koji molds ニホンコウジカビ (日本麹黴) used for food fermentation.