Abstract: Flavonoids, a type of phytochemicals, have been extensively applied to treat and inhabit disease and medically functional disorders as healers, antimicrobial agents, as well as antioxidants. However, their poor water solubility and lipid solubility limit their application. In the present review, multiple methods for modification of flavonids, including glycosylation, deglycosylation, acylation, and methylation, as well as the change of their bioavailability before and after modification are introduced.

Key words: flavoniods, modification methods, biological activity