• They eat bark and buds in winter.

Japanese macaques are omnivorous, collecting and consuming plants, fruits, leaves, seeds, insects, and occasionally small animals. The species obtains food by hand and sometimes uses water for cleaning; their diet includes fruits, leaves, seeds, bark, insects, small vertebrates, cones, and berries. They consume a daily amount of food ranging from 150 grams to 400 grams, with young macaques relying on milk for nourishment. The species’ prey includes beetles, butterflies, flies, Hymenoptera, bedbugs, Orthoptera, dragonflies, stoneflies, Plecoptera, and decapods. Japanese macaques are preyed upon by clouded leopards. In some cultures, the species is consumed as food, but it is not considered halal or kosher.