Daily diet is closely related to human health. The functional ingredients of daily diet play a vital role in regulating the activity of the body， which have become a hot spot of concern， but the specific mechanism is still unclear. microRNA (miRNA)， a non-coding small RNA， could participate in the regulation of the body's life activities by regulating the expression of target gene. This article mainly starts from miRNA and focuses on miRNA in ginsenosides， resveratrol， catechin， polyunsaturated fatty acids， vitamins and other food and functional ingredients in regulating fat formation， cardiovascular disease， neuroprotection and anti-inflammatory and anti-cancer mechanisms. The aim is to explain the underlying mechanism of food and functional components regulating body activity and improving diseases from the perspective of miRNA， and provide ideas for the prevention of related diseases.